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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * History:4 * Started: Aug 9 by Lawrence Foard (entropy@world.std.com),5 * to allow user process control of SCSI devices.6 * Development Sponsored by Killy Corp. NY NY7 *8 * Original driver (sg.c):9 * Copyright (C) 1992 Lawrence Foard10 * Version 2 and 3 extensions to driver:11 * Copyright (C) 1998 - 2014 Douglas Gilbert12 */13 14static int sg_version_num = 30536; /* 2 digits for each component */15#define SG_VERSION_STR "3.5.36"16 17/*18 * D. P. Gilbert (dgilbert@interlog.com), notes:19 * - scsi logging is available via SCSI_LOG_TIMEOUT macros. First20 * the kernel/module needs to be built with CONFIG_SCSI_LOGGING21 * (otherwise the macros compile to empty statements).22 *23 */24#include <linux/module.h>25 26#include <linux/fs.h>27#include <linux/kernel.h>28#include <linux/sched.h>29#include <linux/string.h>30#include <linux/mm.h>31#include <linux/errno.h>32#include <linux/mtio.h>33#include <linux/ioctl.h>34#include <linux/major.h>35#include <linux/slab.h>36#include <linux/fcntl.h>37#include <linux/init.h>38#include <linux/poll.h>39#include <linux/moduleparam.h>40#include <linux/cdev.h>41#include <linux/idr.h>42#include <linux/seq_file.h>43#include <linux/blkdev.h>44#include <linux/delay.h>45#include <linux/blktrace_api.h>46#include <linux/mutex.h>47#include <linux/atomic.h>48#include <linux/ratelimit.h>49#include <linux/uio.h>50#include <linux/cred.h> /* for sg_check_file_access() */51 52#include <scsi/scsi.h>53#include <scsi/scsi_cmnd.h>54#include <scsi/scsi_dbg.h>55#include <scsi/scsi_device.h>56#include <scsi/scsi_driver.h>57#include <scsi/scsi_eh.h>58#include <scsi/scsi_host.h>59#include <scsi/scsi_ioctl.h>60#include <scsi/scsi_tcq.h>61#include <scsi/sg.h>62 63#include "scsi_logging.h"64 65#ifdef CONFIG_SCSI_PROC_FS66#include <linux/proc_fs.h>67static char *sg_version_date = "20140603";68 69static int sg_proc_init(void);70#endif71 72#define SG_ALLOW_DIO_DEF 073 74#define SG_MAX_DEVS (1 << MINORBITS)75 76/* SG_MAX_CDB_SIZE should be 260 (spc4r37 section 3.1.30) however the type77 * of sg_io_hdr::cmd_len can only represent 255. All SCSI commands greater78 * than 16 bytes are "variable length" whose length is a multiple of 479 */80#define SG_MAX_CDB_SIZE 25281 82#define SG_DEFAULT_TIMEOUT mult_frac(SG_DEFAULT_TIMEOUT_USER, HZ, USER_HZ)83 84static int sg_big_buff = SG_DEF_RESERVED_SIZE;85/* N.B. This variable is readable and writeable via86 /proc/scsi/sg/def_reserved_size . Each time sg_open() is called a buffer87 of this size (or less if there is not enough memory) will be reserved88 for use by this file descriptor. [Deprecated usage: this variable is also89 readable via /proc/sys/kernel/sg-big-buff if the sg driver is built into90 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 51298 99static int sg_add_device(struct device *);100static void sg_remove_device(struct device *);101 102static DEFINE_IDR(sg_index_idr);103static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock104 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 list_head entry; /* list entry */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 struct mutex f_mutex; /* protect against changes in this fd */146 int timeout; /* defaults to SG_DEFAULT_TIMEOUT */147 int timeout_user; /* defaults to SG_DEFAULT_TIMEOUT_USER */148 Sg_scatter_hold reserve; /* buffer held for this file descriptor */149 struct list_head rq_list; /* head of request list */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 force_packid; /* 1 -> pack_id input to read(), 0 -> ignored */153 char cmd_q; /* 1 -> allow command queuing, 0 -> don't */154 unsigned char next_cmd_len; /* 0: automatic, >0: use on next write() */155 char keep_orphan; /* 0 -> drop orphan (def), 1 -> keep for read() */156 char mmap_called; /* 0 -> mmap() never called on this fd */157 char res_in_use; /* 1 -> 'reserve' array in use */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 char name[DISK_NAME_LEN];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 enum rq_end_io_ret sg_rq_end_io(struct request *rq, blk_status_t status);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, bool *busy);199static Sg_request *sg_add_request(Sg_fd * sfp);200static int sg_remove_request(Sg_fd * sfp, Sg_request * srp);201static Sg_device *sg_get_dev(int dev);202static void sg_device_destroy(struct kref *kref);203 204#define SZ_SG_HEADER sizeof(struct sg_header)205#define SZ_SG_IO_HDR sizeof(sg_io_hdr_t)206#define SZ_SG_IOVEC sizeof(sg_iovec_t)207#define SZ_SG_REQ_INFO sizeof(sg_req_info_t)208 209#define sg_printk(prefix, sdp, fmt, a...) \210 sdev_prefix_printk(prefix, (sdp)->device, (sdp)->name, fmt, ##a)211 212/*213 * The SCSI interfaces that use read() and write() as an asynchronous variant of214 * ioctl(..., SG_IO, ...) are fundamentally unsafe, since there are lots of ways215 * to trigger read() and write() calls from various contexts with elevated216 * privileges. This can lead to kernel memory corruption (e.g. if these217 * interfaces are called through splice()) and privilege escalation inside218 * userspace (e.g. if a process with access to such a device passes a file219 * descriptor to a SUID binary as stdin/stdout/stderr).220 *221 * This function provides protection for the legacy API by restricting the222 * calling context.223 */224static int sg_check_file_access(struct file *filp, const char *caller)225{226 if (filp->f_cred != current_real_cred()) {227 pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",228 caller, task_tgid_vnr(current), current->comm);229 return -EPERM;230 }231 return 0;232}233 234static int sg_allow_access(struct file *filp, unsigned char *cmd)235{236 struct sg_fd *sfp = filp->private_data;237 238 if (sfp->parentdp->device->type == TYPE_SCANNER)239 return 0;240 if (!scsi_cmd_allowed(cmd, filp->f_mode & FMODE_WRITE))241 return -EPERM;242 return 0;243}244 245static int246open_wait(Sg_device *sdp, int flags)247{248 int retval = 0;249 250 if (flags & O_EXCL) {251 while (sdp->open_cnt > 0) {252 mutex_unlock(&sdp->open_rel_lock);253 retval = wait_event_interruptible(sdp->open_wait,254 (atomic_read(&sdp->detaching) ||255 !sdp->open_cnt));256 mutex_lock(&sdp->open_rel_lock);257 258 if (retval) /* -ERESTARTSYS */259 return retval;260 if (atomic_read(&sdp->detaching))261 return -ENODEV;262 }263 } else {264 while (sdp->exclude) {265 mutex_unlock(&sdp->open_rel_lock);266 retval = wait_event_interruptible(sdp->open_wait,267 (atomic_read(&sdp->detaching) ||268 !sdp->exclude));269 mutex_lock(&sdp->open_rel_lock);270 271 if (retval) /* -ERESTARTSYS */272 return retval;273 if (atomic_read(&sdp->detaching))274 return -ENODEV;275 }276 }277 278 return retval;279}280 281/* Returns 0 on success, else a negated errno value */282static int283sg_open(struct inode *inode, struct file *filp)284{285 int dev = iminor(inode);286 int flags = filp->f_flags;287 struct request_queue *q;288 struct scsi_device *device;289 Sg_device *sdp;290 Sg_fd *sfp;291 int retval;292 293 nonseekable_open(inode, filp);294 if ((flags & O_EXCL) && (O_RDONLY == (flags & O_ACCMODE)))295 return -EPERM; /* Can't lock it with read only access */296 sdp = sg_get_dev(dev);297 if (IS_ERR(sdp))298 return PTR_ERR(sdp);299 300 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,301 "sg_open: flags=0x%x\n", flags));302 303 /* This driver's module count bumped by fops_get in <linux/fs.h> */304 /* Prevent the device driver from vanishing while we sleep */305 device = sdp->device;306 retval = scsi_device_get(device);307 if (retval)308 goto sg_put;309 310 retval = scsi_autopm_get_device(device);311 if (retval)312 goto sdp_put;313 314 /* scsi_block_when_processing_errors() may block so bypass315 * check if O_NONBLOCK. Permits SCSI commands to be issued316 * during error recovery. Tread carefully. */317 if (!((flags & O_NONBLOCK) ||318 scsi_block_when_processing_errors(device))) {319 retval = -ENXIO;320 /* we are in error recovery for this device */321 goto error_out;322 }323 324 mutex_lock(&sdp->open_rel_lock);325 if (flags & O_NONBLOCK) {326 if (flags & O_EXCL) {327 if (sdp->open_cnt > 0) {328 retval = -EBUSY;329 goto error_mutex_locked;330 }331 } else {332 if (sdp->exclude) {333 retval = -EBUSY;334 goto error_mutex_locked;335 }336 }337 } else {338 retval = open_wait(sdp, flags);339 if (retval) /* -ERESTARTSYS or -ENODEV */340 goto error_mutex_locked;341 }342 343 /* N.B. at this point we are holding the open_rel_lock */344 if (flags & O_EXCL)345 sdp->exclude = true;346 347 if (sdp->open_cnt < 1) { /* no existing opens */348 sdp->sgdebug = 0;349 q = device->request_queue;350 sdp->sg_tablesize = queue_max_segments(q);351 }352 sfp = sg_add_sfp(sdp);353 if (IS_ERR(sfp)) {354 retval = PTR_ERR(sfp);355 goto out_undo;356 }357 358 filp->private_data = sfp;359 sdp->open_cnt++;360 mutex_unlock(&sdp->open_rel_lock);361 362 retval = 0;363sg_put:364 kref_put(&sdp->d_ref, sg_device_destroy);365 return retval;366 367out_undo:368 if (flags & O_EXCL) {369 sdp->exclude = false; /* undo if error */370 wake_up_interruptible(&sdp->open_wait);371 }372error_mutex_locked:373 mutex_unlock(&sdp->open_rel_lock);374error_out:375 scsi_autopm_put_device(device);376sdp_put:377 kref_put(&sdp->d_ref, sg_device_destroy);378 scsi_device_put(device);379 return retval;380}381 382/* Release resources associated with a successful sg_open()383 * Returns 0 on success, else a negated errno value */384static int385sg_release(struct inode *inode, struct file *filp)386{387 Sg_device *sdp;388 Sg_fd *sfp;389 390 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))391 return -ENXIO;392 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_release\n"));393 394 mutex_lock(&sdp->open_rel_lock);395 scsi_autopm_put_device(sdp->device);396 kref_put(&sfp->f_ref, sg_remove_sfp);397 sdp->open_cnt--;398 399 /* possibly many open()s waiting on exlude clearing, start many;400 * only open(O_EXCL)s wait on 0==open_cnt so only start one */401 if (sdp->exclude) {402 sdp->exclude = false;403 wake_up_interruptible_all(&sdp->open_wait);404 } else if (0 == sdp->open_cnt) {405 wake_up_interruptible(&sdp->open_wait);406 }407 mutex_unlock(&sdp->open_rel_lock);408 return 0;409}410 411static int get_sg_io_pack_id(int *pack_id, void __user *buf, size_t count)412{413 struct sg_header __user *old_hdr = buf;414 int reply_len;415 416 if (count >= SZ_SG_HEADER) {417 /* negative reply_len means v3 format, otherwise v1/v2 */418 if (get_user(reply_len, &old_hdr->reply_len))419 return -EFAULT;420 421 if (reply_len >= 0)422 return get_user(*pack_id, &old_hdr->pack_id);423 424 if (in_compat_syscall() &&425 count >= sizeof(struct compat_sg_io_hdr)) {426 struct compat_sg_io_hdr __user *hp = buf;427 428 return get_user(*pack_id, &hp->pack_id);429 }430 431 if (count >= sizeof(struct sg_io_hdr)) {432 struct sg_io_hdr __user *hp = buf;433 434 return get_user(*pack_id, &hp->pack_id);435 }436 }437 438 /* no valid header was passed, so ignore the pack_id */439 *pack_id = -1;440 return 0;441}442 443static ssize_t444sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)445{446 Sg_device *sdp;447 Sg_fd *sfp;448 Sg_request *srp;449 int req_pack_id = -1;450 bool busy;451 sg_io_hdr_t *hp;452 struct sg_header *old_hdr;453 int retval;454 455 /*456 * This could cause a response to be stranded. Close the associated457 * file descriptor to free up any resources being held.458 */459 retval = sg_check_file_access(filp, __func__);460 if (retval)461 return retval;462 463 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))464 return -ENXIO;465 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,466 "sg_read: count=%d\n", (int) count));467 468 if (sfp->force_packid)469 retval = get_sg_io_pack_id(&req_pack_id, buf, count);470 if (retval)471 return retval;472 473 srp = sg_get_rq_mark(sfp, req_pack_id, &busy);474 if (!srp) { /* now wait on packet to arrive */475 if (filp->f_flags & O_NONBLOCK)476 return -EAGAIN;477 retval = wait_event_interruptible(sfp->read_wait,478 ((srp = sg_get_rq_mark(sfp, req_pack_id, &busy)) ||479 (!busy && atomic_read(&sdp->detaching))));480 if (!srp)481 /* signal or detaching */482 return retval ? retval : -ENODEV;483 }484 if (srp->header.interface_id != '\0')485 return sg_new_read(sfp, buf, count, srp);486 487 hp = &srp->header;488 old_hdr = kzalloc(SZ_SG_HEADER, GFP_KERNEL);489 if (!old_hdr)490 return -ENOMEM;491 492 old_hdr->reply_len = (int) hp->timeout;493 old_hdr->pack_len = old_hdr->reply_len; /* old, strange behaviour */494 old_hdr->pack_id = hp->pack_id;495 old_hdr->twelve_byte =496 ((srp->data.cmd_opcode >= 0xc0) && (12 == hp->cmd_len)) ? 1 : 0;497 old_hdr->target_status = hp->masked_status;498 old_hdr->host_status = hp->host_status;499 old_hdr->driver_status = hp->driver_status;500 if ((CHECK_CONDITION & hp->masked_status) ||501 (srp->sense_b[0] & 0x70) == 0x70) {502 old_hdr->driver_status = DRIVER_SENSE;503 memcpy(old_hdr->sense_buffer, srp->sense_b,504 sizeof (old_hdr->sense_buffer));505 }506 switch (hp->host_status) {507 /* This setup of 'result' is for backward compatibility and is best508 ignored by the user who should use target, host + driver status */509 case DID_OK:510 case DID_PASSTHROUGH:511 case DID_SOFT_ERROR:512 old_hdr->result = 0;513 break;514 case DID_NO_CONNECT:515 case DID_BUS_BUSY:516 case DID_TIME_OUT:517 old_hdr->result = EBUSY;518 break;519 case DID_BAD_TARGET:520 case DID_ABORT:521 case DID_PARITY:522 case DID_RESET:523 case DID_BAD_INTR:524 old_hdr->result = EIO;525 break;526 case DID_ERROR:527 old_hdr->result = (srp->sense_b[0] == 0 && 528 hp->masked_status == GOOD) ? 0 : EIO;529 break;530 default:531 old_hdr->result = EIO;532 break;533 }534 535 /* Now copy the result back to the user buffer. */536 if (count >= SZ_SG_HEADER) {537 if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) {538 retval = -EFAULT;539 goto free_old_hdr;540 }541 buf += SZ_SG_HEADER;542 if (count > old_hdr->reply_len)543 count = old_hdr->reply_len;544 if (count > SZ_SG_HEADER) {545 if (sg_read_oxfer(srp, buf, count - SZ_SG_HEADER)) {546 retval = -EFAULT;547 goto free_old_hdr;548 }549 }550 } else551 count = (old_hdr->result == 0) ? 0 : -EIO;552 sg_finish_rem_req(srp);553 sg_remove_request(sfp, srp);554 retval = count;555free_old_hdr:556 kfree(old_hdr);557 return retval;558}559 560static ssize_t561sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)562{563 sg_io_hdr_t *hp = &srp->header;564 int err = 0, err2;565 int len;566 567 if (in_compat_syscall()) {568 if (count < sizeof(struct compat_sg_io_hdr)) {569 err = -EINVAL;570 goto err_out;571 }572 } else if (count < SZ_SG_IO_HDR) {573 err = -EINVAL;574 goto err_out;575 }576 hp->sb_len_wr = 0;577 if ((hp->mx_sb_len > 0) && hp->sbp) {578 if ((CHECK_CONDITION & hp->masked_status) ||579 (srp->sense_b[0] & 0x70) == 0x70) {580 int sb_len = SCSI_SENSE_BUFFERSIZE;581 sb_len = (hp->mx_sb_len > sb_len) ? sb_len : hp->mx_sb_len;582 len = 8 + (int) srp->sense_b[7]; /* Additional sense length field */583 len = (len > sb_len) ? sb_len : len;584 if (copy_to_user(hp->sbp, srp->sense_b, len)) {585 err = -EFAULT;586 goto err_out;587 }588 hp->driver_status = DRIVER_SENSE;589 hp->sb_len_wr = len;590 }591 }592 if (hp->masked_status || hp->host_status || hp->driver_status)593 hp->info |= SG_INFO_CHECK;594 err = put_sg_io_hdr(hp, buf);595err_out:596 err2 = sg_finish_rem_req(srp);597 sg_remove_request(sfp, srp);598 return err ? : err2 ? : count;599}600 601static ssize_t602sg_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)603{604 int mxsize, cmd_size, k;605 int input_size, blocking;606 unsigned char opcode;607 Sg_device *sdp;608 Sg_fd *sfp;609 Sg_request *srp;610 struct sg_header old_hdr;611 sg_io_hdr_t *hp;612 unsigned char cmnd[SG_MAX_CDB_SIZE];613 int retval;614 615 retval = sg_check_file_access(filp, __func__);616 if (retval)617 return retval;618 619 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))620 return -ENXIO;621 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,622 "sg_write: count=%d\n", (int) count));623 if (atomic_read(&sdp->detaching))624 return -ENODEV;625 if (!((filp->f_flags & O_NONBLOCK) ||626 scsi_block_when_processing_errors(sdp->device)))627 return -ENXIO;628 629 if (count < SZ_SG_HEADER)630 return -EIO;631 if (copy_from_user(&old_hdr, buf, SZ_SG_HEADER))632 return -EFAULT;633 blocking = !(filp->f_flags & O_NONBLOCK);634 if (old_hdr.reply_len < 0)635 return sg_new_write(sfp, filp, buf, count,636 blocking, 0, 0, NULL);637 if (count < (SZ_SG_HEADER + 6))638 return -EIO; /* The minimum scsi command length is 6 bytes. */639 640 buf += SZ_SG_HEADER;641 if (get_user(opcode, buf))642 return -EFAULT;643 644 if (!(srp = sg_add_request(sfp))) {645 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sdp,646 "sg_write: queue full\n"));647 return -EDOM;648 }649 mutex_lock(&sfp->f_mutex);650 if (sfp->next_cmd_len > 0) {651 cmd_size = sfp->next_cmd_len;652 sfp->next_cmd_len = 0; /* reset so only this write() effected */653 } else {654 cmd_size = COMMAND_SIZE(opcode); /* based on SCSI command group */655 if ((opcode >= 0xc0) && old_hdr.twelve_byte)656 cmd_size = 12;657 }658 mutex_unlock(&sfp->f_mutex);659 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,660 "sg_write: scsi opcode=0x%02x, cmd_size=%d\n", (int) opcode, cmd_size));661/* Determine buffer size. */662 input_size = count - cmd_size;663 mxsize = (input_size > old_hdr.reply_len) ? input_size : old_hdr.reply_len;664 mxsize -= SZ_SG_HEADER;665 input_size -= SZ_SG_HEADER;666 if (input_size < 0) {667 sg_remove_request(sfp, srp);668 return -EIO; /* User did not pass enough bytes for this command. */669 }670 hp = &srp->header;671 hp->interface_id = '\0'; /* indicator of old interface tunnelled */672 hp->cmd_len = (unsigned char) cmd_size;673 hp->iovec_count = 0;674 hp->mx_sb_len = 0;675 if (input_size > 0)676 hp->dxfer_direction = (old_hdr.reply_len > SZ_SG_HEADER) ?677 SG_DXFER_TO_FROM_DEV : SG_DXFER_TO_DEV;678 else679 hp->dxfer_direction = (mxsize > 0) ? SG_DXFER_FROM_DEV : SG_DXFER_NONE;680 hp->dxfer_len = mxsize;681 if ((hp->dxfer_direction == SG_DXFER_TO_DEV) ||682 (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV))683 hp->dxferp = (char __user *)buf + cmd_size;684 else685 hp->dxferp = NULL;686 hp->sbp = NULL;687 hp->timeout = old_hdr.reply_len; /* structure abuse ... */688 hp->flags = input_size; /* structure abuse ... */689 hp->pack_id = old_hdr.pack_id;690 hp->usr_ptr = NULL;691 if (copy_from_user(cmnd, buf, cmd_size)) {692 sg_remove_request(sfp, srp);693 return -EFAULT;694 }695 /*696 * SG_DXFER_TO_FROM_DEV is functionally equivalent to SG_DXFER_FROM_DEV,697 * but is is possible that the app intended SG_DXFER_TO_DEV, because there698 * is a non-zero input_size, so emit a warning.699 */700 if (hp->dxfer_direction == SG_DXFER_TO_FROM_DEV) {701 printk_ratelimited(KERN_WARNING702 "sg_write: data in/out %d/%d bytes "703 "for SCSI command 0x%x-- guessing "704 "data in;\n program %s not setting "705 "count and/or reply_len properly\n",706 old_hdr.reply_len - (int)SZ_SG_HEADER,707 input_size, (unsigned int) cmnd[0],708 current->comm);709 }710 k = sg_common_write(sfp, srp, cmnd, sfp->timeout, blocking);711 return (k < 0) ? k : count;712}713 714static ssize_t715sg_new_write(Sg_fd *sfp, struct file *file, const char __user *buf,716 size_t count, int blocking, int read_only, int sg_io_owned,717 Sg_request **o_srp)718{719 int k;720 Sg_request *srp;721 sg_io_hdr_t *hp;722 unsigned char cmnd[SG_MAX_CDB_SIZE];723 int timeout;724 unsigned long ul_timeout;725 726 if (count < SZ_SG_IO_HDR)727 return -EINVAL;728 729 sfp->cmd_q = 1; /* when sg_io_hdr seen, set command queuing on */730 if (!(srp = sg_add_request(sfp))) {731 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,732 "sg_new_write: queue full\n"));733 return -EDOM;734 }735 srp->sg_io_owned = sg_io_owned;736 hp = &srp->header;737 if (get_sg_io_hdr(hp, buf)) {738 sg_remove_request(sfp, srp);739 return -EFAULT;740 }741 if (hp->interface_id != 'S') {742 sg_remove_request(sfp, srp);743 return -ENOSYS;744 }745 if (hp->flags & SG_FLAG_MMAP_IO) {746 if (hp->dxfer_len > sfp->reserve.bufflen) {747 sg_remove_request(sfp, srp);748 return -ENOMEM; /* MMAP_IO size must fit in reserve buffer */749 }750 if (hp->flags & SG_FLAG_DIRECT_IO) {751 sg_remove_request(sfp, srp);752 return -EINVAL; /* either MMAP_IO or DIRECT_IO (not both) */753 }754 if (sfp->res_in_use) {755 sg_remove_request(sfp, srp);756 return -EBUSY; /* reserve buffer already being used */757 }758 }759 ul_timeout = msecs_to_jiffies(srp->header.timeout);760 timeout = (ul_timeout < INT_MAX) ? ul_timeout : INT_MAX;761 if ((!hp->cmdp) || (hp->cmd_len < 6) || (hp->cmd_len > sizeof (cmnd))) {762 sg_remove_request(sfp, srp);763 return -EMSGSIZE;764 }765 if (copy_from_user(cmnd, hp->cmdp, hp->cmd_len)) {766 sg_remove_request(sfp, srp);767 return -EFAULT;768 }769 if (read_only && sg_allow_access(file, cmnd)) {770 sg_remove_request(sfp, srp);771 return -EPERM;772 }773 k = sg_common_write(sfp, srp, cmnd, timeout, blocking);774 if (k < 0)775 return k;776 if (o_srp)777 *o_srp = srp;778 return count;779}780 781static int782sg_common_write(Sg_fd * sfp, Sg_request * srp,783 unsigned char *cmnd, int timeout, int blocking)784{785 int k, at_head;786 Sg_device *sdp = sfp->parentdp;787 sg_io_hdr_t *hp = &srp->header;788 789 srp->data.cmd_opcode = cmnd[0]; /* hold opcode of command */790 hp->status = 0;791 hp->masked_status = 0;792 hp->msg_status = 0;793 hp->info = 0;794 hp->host_status = 0;795 hp->driver_status = 0;796 hp->resid = 0;797 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,798 "sg_common_write: scsi opcode=0x%02x, cmd_size=%d\n",799 (int) cmnd[0], (int) hp->cmd_len));800 801 if (hp->dxfer_len >= SZ_256M) {802 sg_remove_request(sfp, srp);803 return -EINVAL;804 }805 806 k = sg_start_req(srp, cmnd);807 if (k) {808 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,809 "sg_common_write: start_req err=%d\n", k));810 sg_finish_rem_req(srp);811 sg_remove_request(sfp, srp);812 return k; /* probably out of space --> ENOMEM */813 }814 if (atomic_read(&sdp->detaching)) {815 if (srp->bio) {816 blk_mq_free_request(srp->rq);817 srp->rq = NULL;818 }819 820 sg_finish_rem_req(srp);821 sg_remove_request(sfp, srp);822 return -ENODEV;823 }824 825 hp->duration = jiffies_to_msecs(jiffies);826 if (hp->interface_id != '\0' && /* v3 (or later) interface */827 (SG_FLAG_Q_AT_TAIL & hp->flags))828 at_head = 0;829 else830 at_head = 1;831 832 srp->rq->timeout = timeout;833 kref_get(&sfp->f_ref); /* sg_rq_end_io() does kref_put(). */834 srp->rq->end_io = sg_rq_end_io;835 blk_execute_rq_nowait(srp->rq, at_head);836 return 0;837}838 839static int srp_done(Sg_fd *sfp, Sg_request *srp)840{841 unsigned long flags;842 int ret;843 844 read_lock_irqsave(&sfp->rq_list_lock, flags);845 ret = srp->done;846 read_unlock_irqrestore(&sfp->rq_list_lock, flags);847 return ret;848}849 850static int max_sectors_bytes(struct request_queue *q)851{852 unsigned int max_sectors = queue_max_sectors(q);853 854 max_sectors = min_t(unsigned int, max_sectors, INT_MAX >> 9);855 856 return max_sectors << 9;857}858 859static void860sg_fill_request_table(Sg_fd *sfp, sg_req_info_t *rinfo)861{862 Sg_request *srp;863 int val;864 unsigned int ms;865 866 val = 0;867 list_for_each_entry(srp, &sfp->rq_list, entry) {868 if (val >= SG_MAX_QUEUE)869 break;870 rinfo[val].req_state = srp->done + 1;871 rinfo[val].problem =872 srp->header.masked_status &873 srp->header.host_status &874 srp->header.driver_status;875 if (srp->done)876 rinfo[val].duration =877 srp->header.duration;878 else {879 ms = jiffies_to_msecs(jiffies);880 rinfo[val].duration =881 (ms > srp->header.duration) ?882 (ms - srp->header.duration) : 0;883 }884 rinfo[val].orphan = srp->orphan;885 rinfo[val].sg_io_owned = srp->sg_io_owned;886 rinfo[val].pack_id = srp->header.pack_id;887 rinfo[val].usr_ptr = srp->header.usr_ptr;888 val++;889 }890}891 892#ifdef CONFIG_COMPAT893struct compat_sg_req_info { /* used by SG_GET_REQUEST_TABLE ioctl() */894 char req_state;895 char orphan;896 char sg_io_owned;897 char problem;898 int pack_id;899 compat_uptr_t usr_ptr;900 unsigned int duration;901 int unused;902};903 904static int put_compat_request_table(struct compat_sg_req_info __user *o,905 struct sg_req_info *rinfo)906{907 int i;908 for (i = 0; i < SG_MAX_QUEUE; i++) {909 if (copy_to_user(o + i, rinfo + i, offsetof(sg_req_info_t, usr_ptr)) ||910 put_user((uintptr_t)rinfo[i].usr_ptr, &o[i].usr_ptr) ||911 put_user(rinfo[i].duration, &o[i].duration) ||912 put_user(rinfo[i].unused, &o[i].unused))913 return -EFAULT;914 }915 return 0;916}917#endif918 919static long920sg_ioctl_common(struct file *filp, Sg_device *sdp, Sg_fd *sfp,921 unsigned int cmd_in, void __user *p)922{923 int __user *ip = p;924 int result, val, read_only;925 Sg_request *srp;926 unsigned long iflags;927 928 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,929 "sg_ioctl: cmd=0x%x\n", (int) cmd_in));930 read_only = (O_RDWR != (filp->f_flags & O_ACCMODE));931 932 switch (cmd_in) {933 case SG_IO:934 if (atomic_read(&sdp->detaching))935 return -ENODEV;936 if (!scsi_block_when_processing_errors(sdp->device))937 return -ENXIO;938 result = sg_new_write(sfp, filp, p, SZ_SG_IO_HDR,939 1, read_only, 1, &srp);940 if (result < 0)941 return result;942 result = wait_event_interruptible(sfp->read_wait,943 srp_done(sfp, srp));944 write_lock_irq(&sfp->rq_list_lock);945 if (srp->done) {946 srp->done = 2;947 write_unlock_irq(&sfp->rq_list_lock);948 result = sg_new_read(sfp, p, SZ_SG_IO_HDR, srp);949 return (result < 0) ? result : 0;950 }951 srp->orphan = 1;952 write_unlock_irq(&sfp->rq_list_lock);953 return result; /* -ERESTARTSYS because signal hit process */954 case SG_SET_TIMEOUT:955 result = get_user(val, ip);956 if (result)957 return result;958 if (val < 0)959 return -EIO;960 if (val >= mult_frac((s64)INT_MAX, USER_HZ, HZ))961 val = min_t(s64, mult_frac((s64)INT_MAX, USER_HZ, HZ),962 INT_MAX);963 sfp->timeout_user = val;964 sfp->timeout = mult_frac(val, HZ, USER_HZ);965 966 return 0;967 case SG_GET_TIMEOUT: /* N.B. User receives timeout as return value */968 /* strange ..., for backward compatibility */969 return sfp->timeout_user;970 case SG_SET_FORCE_LOW_DMA:971 /*972 * N.B. This ioctl never worked properly, but failed to973 * return an error value. So returning '0' to keep compability974 * with legacy applications.975 */976 return 0;977 case SG_GET_LOW_DMA:978 return put_user(0, ip);979 case SG_GET_SCSI_ID:980 {981 sg_scsi_id_t v;982 983 if (atomic_read(&sdp->detaching))984 return -ENODEV;985 memset(&v, 0, sizeof(v));986 v.host_no = sdp->device->host->host_no;987 v.channel = sdp->device->channel;988 v.scsi_id = sdp->device->id;989 v.lun = sdp->device->lun;990 v.scsi_type = sdp->device->type;991 v.h_cmd_per_lun = sdp->device->host->cmd_per_lun;992 v.d_queue_depth = sdp->device->queue_depth;993 if (copy_to_user(p, &v, sizeof(sg_scsi_id_t)))994 return -EFAULT;995 return 0;996 }997 case SG_SET_FORCE_PACK_ID:998 result = get_user(val, ip);999 if (result)1000 return result;1001 sfp->force_packid = val ? 1 : 0;1002 return 0;1003 case SG_GET_PACK_ID:1004 read_lock_irqsave(&sfp->rq_list_lock, iflags);1005 list_for_each_entry(srp, &sfp->rq_list, entry) {1006 if ((1 == srp->done) && (!srp->sg_io_owned)) {1007 read_unlock_irqrestore(&sfp->rq_list_lock,1008 iflags);1009 return put_user(srp->header.pack_id, ip);1010 }1011 }1012 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);1013 return put_user(-1, ip);1014 case SG_GET_NUM_WAITING:1015 read_lock_irqsave(&sfp->rq_list_lock, iflags);1016 val = 0;1017 list_for_each_entry(srp, &sfp->rq_list, entry) {1018 if ((1 == srp->done) && (!srp->sg_io_owned))1019 ++val;1020 }1021 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);1022 return put_user(val, ip);1023 case SG_GET_SG_TABLESIZE:1024 return put_user(sdp->sg_tablesize, ip);1025 case SG_SET_RESERVED_SIZE:1026 result = get_user(val, ip);1027 if (result)1028 return result;1029 if (val < 0)1030 return -EINVAL;1031 val = min_t(int, val,1032 max_sectors_bytes(sdp->device->request_queue));1033 mutex_lock(&sfp->f_mutex);1034 if (val != sfp->reserve.bufflen) {1035 if (sfp->mmap_called ||1036 sfp->res_in_use) {1037 mutex_unlock(&sfp->f_mutex);1038 return -EBUSY;1039 }1040 1041 sg_remove_scat(sfp, &sfp->reserve);1042 sg_build_reserve(sfp, val);1043 }1044 mutex_unlock(&sfp->f_mutex);1045 return 0;1046 case SG_GET_RESERVED_SIZE:1047 val = min_t(int, sfp->reserve.bufflen,1048 max_sectors_bytes(sdp->device->request_queue));1049 return put_user(val, ip);1050 case SG_SET_COMMAND_Q:1051 result = get_user(val, ip);1052 if (result)1053 return result;1054 sfp->cmd_q = val ? 1 : 0;1055 return 0;1056 case SG_GET_COMMAND_Q:1057 return put_user((int) sfp->cmd_q, ip);1058 case SG_SET_KEEP_ORPHAN:1059 result = get_user(val, ip);1060 if (result)1061 return result;1062 sfp->keep_orphan = val;1063 return 0;1064 case SG_GET_KEEP_ORPHAN:1065 return put_user((int) sfp->keep_orphan, ip);1066 case SG_NEXT_CMD_LEN:1067 result = get_user(val, ip);1068 if (result)1069 return result;1070 if (val > SG_MAX_CDB_SIZE)1071 return -ENOMEM;1072 sfp->next_cmd_len = (val > 0) ? val : 0;1073 return 0;1074 case SG_GET_VERSION_NUM:1075 return put_user(sg_version_num, ip);1076 case SG_GET_ACCESS_COUNT:1077 /* faked - we don't have a real access count anymore */1078 val = (sdp->device ? 1 : 0);1079 return put_user(val, ip);1080 case SG_GET_REQUEST_TABLE:1081 {1082 sg_req_info_t *rinfo;1083 1084 rinfo = kcalloc(SG_MAX_QUEUE, SZ_SG_REQ_INFO,1085 GFP_KERNEL);1086 if (!rinfo)1087 return -ENOMEM;1088 read_lock_irqsave(&sfp->rq_list_lock, iflags);1089 sg_fill_request_table(sfp, rinfo);1090 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);1091 #ifdef CONFIG_COMPAT1092 if (in_compat_syscall())1093 result = put_compat_request_table(p, rinfo);1094 else1095 #endif1096 result = copy_to_user(p, rinfo,1097 SZ_SG_REQ_INFO * SG_MAX_QUEUE);1098 result = result ? -EFAULT : 0;1099 kfree(rinfo);1100 return result;1101 }1102 case SG_EMULATED_HOST:1103 if (atomic_read(&sdp->detaching))1104 return -ENODEV;1105 return put_user(sdp->device->host->hostt->emulated, ip);1106 case SCSI_IOCTL_SEND_COMMAND:1107 if (atomic_read(&sdp->detaching))1108 return -ENODEV;1109 return scsi_ioctl(sdp->device, filp->f_mode & FMODE_WRITE,1110 cmd_in, p);1111 case SG_SET_DEBUG:1112 result = get_user(val, ip);1113 if (result)1114 return result;1115 sdp->sgdebug = (char) val;1116 return 0;1117 case BLKSECTGET:1118 return put_user(max_sectors_bytes(sdp->device->request_queue),1119 ip);1120 case BLKTRACESETUP:1121 return blk_trace_setup(sdp->device->request_queue, sdp->name,1122 MKDEV(SCSI_GENERIC_MAJOR, sdp->index),1123 NULL, p);1124 case BLKTRACESTART:1125 return blk_trace_startstop(sdp->device->request_queue, 1);1126 case BLKTRACESTOP:1127 return blk_trace_startstop(sdp->device->request_queue, 0);1128 case BLKTRACETEARDOWN:1129 return blk_trace_remove(sdp->device->request_queue);1130 case SCSI_IOCTL_GET_IDLUN:1131 case SCSI_IOCTL_GET_BUS_NUMBER:1132 case SCSI_IOCTL_PROBE_HOST:1133 case SG_GET_TRANSFORM:1134 case SG_SCSI_RESET:1135 if (atomic_read(&sdp->detaching))1136 return -ENODEV;1137 break;1138 default:1139 if (read_only)1140 return -EPERM; /* don't know so take safe approach */1141 break;1142 }1143 1144 result = scsi_ioctl_block_when_processing_errors(sdp->device,1145 cmd_in, filp->f_flags & O_NDELAY);1146 if (result)1147 return result;1148 1149 return -ENOIOCTLCMD;1150}1151 1152static long1153sg_ioctl(struct file *filp, unsigned int cmd_in, unsigned long arg)1154{1155 void __user *p = (void __user *)arg;1156 Sg_device *sdp;1157 Sg_fd *sfp;1158 int ret;1159 1160 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))1161 return -ENXIO;1162 1163 ret = sg_ioctl_common(filp, sdp, sfp, cmd_in, p);1164 if (ret != -ENOIOCTLCMD)1165 return ret;1166 return scsi_ioctl(sdp->device, filp->f_mode & FMODE_WRITE, cmd_in, p);1167}1168 1169static __poll_t1170sg_poll(struct file *filp, poll_table * wait)1171{1172 __poll_t res = 0;1173 Sg_device *sdp;1174 Sg_fd *sfp;1175 Sg_request *srp;1176 int count = 0;1177 unsigned long iflags;1178 1179 sfp = filp->private_data;1180 if (!sfp)1181 return EPOLLERR;1182 sdp = sfp->parentdp;1183 if (!sdp)1184 return EPOLLERR;1185 poll_wait(filp, &sfp->read_wait, wait);1186 read_lock_irqsave(&sfp->rq_list_lock, iflags);1187 list_for_each_entry(srp, &sfp->rq_list, entry) {1188 /* if any read waiting, flag it */1189 if ((0 == res) && (1 == srp->done) && (!srp->sg_io_owned))1190 res = EPOLLIN | EPOLLRDNORM;1191 ++count;1192 }1193 read_unlock_irqrestore(&sfp->rq_list_lock, iflags);1194 1195 if (atomic_read(&sdp->detaching))1196 res |= EPOLLHUP;1197 else if (!sfp->cmd_q) {1198 if (0 == count)1199 res |= EPOLLOUT | EPOLLWRNORM;1200 } else if (count < SG_MAX_QUEUE)1201 res |= EPOLLOUT | EPOLLWRNORM;1202 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,1203 "sg_poll: res=0x%x\n", (__force u32) res));1204 return res;1205}1206 1207static int1208sg_fasync(int fd, struct file *filp, int mode)1209{1210 Sg_device *sdp;1211 Sg_fd *sfp;1212 1213 if ((!(sfp = (Sg_fd *) filp->private_data)) || (!(sdp = sfp->parentdp)))1214 return -ENXIO;1215 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,1216 "sg_fasync: mode=%d\n", mode));1217 1218 return fasync_helper(fd, filp, mode, &sfp->async_qp);1219}1220 1221static vm_fault_t1222sg_vma_fault(struct vm_fault *vmf)1223{1224 struct vm_area_struct *vma = vmf->vma;1225 Sg_fd *sfp;1226 unsigned long offset, len, sa;1227 Sg_scatter_hold *rsv_schp;1228 int k, length;1229 1230 if ((NULL == vma) || (!(sfp = (Sg_fd *) vma->vm_private_data)))1231 return VM_FAULT_SIGBUS;1232 rsv_schp = &sfp->reserve;1233 offset = vmf->pgoff << PAGE_SHIFT;1234 if (offset >= rsv_schp->bufflen)1235 return VM_FAULT_SIGBUS;1236 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,1237 "sg_vma_fault: offset=%lu, scatg=%d\n",1238 offset, rsv_schp->k_use_sg));1239 sa = vma->vm_start;1240 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);1241 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {1242 len = vma->vm_end - sa;1243 len = (len < length) ? len : length;1244 if (offset < len) {1245 struct page *page = nth_page(rsv_schp->pages[k],1246 offset >> PAGE_SHIFT);1247 get_page(page); /* increment page count */1248 vmf->page = page;1249 return 0; /* success */1250 }1251 sa += len;1252 offset -= len;1253 }1254 1255 return VM_FAULT_SIGBUS;1256}1257 1258static const struct vm_operations_struct sg_mmap_vm_ops = {1259 .fault = sg_vma_fault,1260};1261 1262static int1263sg_mmap(struct file *filp, struct vm_area_struct *vma)1264{1265 Sg_fd *sfp;1266 unsigned long req_sz, len, sa;1267 Sg_scatter_hold *rsv_schp;1268 int k, length;1269 int ret = 0;1270 1271 if ((!filp) || (!vma) || (!(sfp = (Sg_fd *) filp->private_data)))1272 return -ENXIO;1273 req_sz = vma->vm_end - vma->vm_start;1274 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sfp->parentdp,1275 "sg_mmap starting, vm_start=%p, len=%d\n",1276 (void *) vma->vm_start, (int) req_sz));1277 if (vma->vm_pgoff)1278 return -EINVAL; /* want no offset */1279 rsv_schp = &sfp->reserve;1280 mutex_lock(&sfp->f_mutex);1281 if (req_sz > rsv_schp->bufflen) {1282 ret = -ENOMEM; /* cannot map more than reserved buffer */1283 goto out;1284 }1285 1286 sa = vma->vm_start;1287 length = 1 << (PAGE_SHIFT + rsv_schp->page_order);1288 for (k = 0; k < rsv_schp->k_use_sg && sa < vma->vm_end; k++) {1289 len = vma->vm_end - sa;1290 len = (len < length) ? len : length;1291 sa += len;1292 }1293 1294 sfp->mmap_called = 1;1295 vm_flags_set(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP);1296 vma->vm_private_data = sfp;1297 vma->vm_ops = &sg_mmap_vm_ops;1298out:1299 mutex_unlock(&sfp->f_mutex);1300 return ret;1301}1302 1303static void1304sg_rq_end_io_usercontext(struct work_struct *work)1305{1306 struct sg_request *srp = container_of(work, struct sg_request, ew.work);1307 struct sg_fd *sfp = srp->parentfp;1308 1309 sg_finish_rem_req(srp);1310 sg_remove_request(sfp, srp);1311 kref_put(&sfp->f_ref, sg_remove_sfp);1312}1313 1314/*1315 * This function is a "bottom half" handler that is called by the mid1316 * level when a command is completed (or has failed).1317 */1318static enum rq_end_io_ret1319sg_rq_end_io(struct request *rq, blk_status_t status)1320{1321 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);1322 struct sg_request *srp = rq->end_io_data;1323 Sg_device *sdp;1324 Sg_fd *sfp;1325 unsigned long iflags;1326 unsigned int ms;1327 char *sense;1328 int result, resid, done = 1;1329 1330 if (WARN_ON(srp->done != 0))1331 return RQ_END_IO_NONE;1332 1333 sfp = srp->parentfp;1334 if (WARN_ON(sfp == NULL))1335 return RQ_END_IO_NONE;1336 1337 sdp = sfp->parentdp;1338 if (unlikely(atomic_read(&sdp->detaching)))1339 pr_info("%s: device detaching\n", __func__);1340 1341 sense = scmd->sense_buffer;1342 result = scmd->result;1343 resid = scmd->resid_len;1344 1345 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sdp,1346 "sg_cmd_done: pack_id=%d, res=0x%x\n",1347 srp->header.pack_id, result));1348 srp->header.resid = resid;1349 ms = jiffies_to_msecs(jiffies);1350 srp->header.duration = (ms > srp->header.duration) ?1351 (ms - srp->header.duration) : 0;1352 if (0 != result) {1353 struct scsi_sense_hdr sshdr;1354 1355 srp->header.status = 0xff & result;1356 srp->header.masked_status = sg_status_byte(result);1357 srp->header.msg_status = COMMAND_COMPLETE;1358 srp->header.host_status = host_byte(result);1359 srp->header.driver_status = driver_byte(result);1360 if ((sdp->sgdebug > 0) &&1361 ((CHECK_CONDITION == srp->header.masked_status) ||1362 (COMMAND_TERMINATED == srp->header.masked_status)))1363 __scsi_print_sense(sdp->device, __func__, sense,1364 SCSI_SENSE_BUFFERSIZE);1365 1366 /* Following if statement is a patch supplied by Eric Youngdale */1367 if (driver_byte(result) != 01368 && scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)1369 && !scsi_sense_is_deferred(&sshdr)1370 && sshdr.sense_key == UNIT_ATTENTION1371 && sdp->device->removable) {1372 /* Detected possible disc change. Set the bit - this */1373 /* may be used if there are filesystems using this device */1374 sdp->device->changed = 1;1375 }1376 }1377 1378 if (scmd->sense_len)1379 memcpy(srp->sense_b, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);1380 1381 /* Rely on write phase to clean out srp status values, so no "else" */1382 1383 /*1384 * Free the request as soon as it is complete so that its resources1385 * can be reused without waiting for userspace to read() the1386 * result. But keep the associated bio (if any) around until1387 * blk_rq_unmap_user() can be called from user context.1388 */1389 srp->rq = NULL;1390 blk_mq_free_request(rq);1391 1392 write_lock_irqsave(&sfp->rq_list_lock, iflags);1393 if (unlikely(srp->orphan)) {1394 if (sfp->keep_orphan)1395 srp->sg_io_owned = 0;1396 else1397 done = 0;1398 }1399 srp->done = done;1400 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);1401 1402 if (likely(done)) {1403 /* Now wake up any sg_read() that is waiting for this1404 * packet.1405 */1406 wake_up_interruptible(&sfp->read_wait);1407 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_IN);1408 kref_put(&sfp->f_ref, sg_remove_sfp);1409 } else {1410 INIT_WORK(&srp->ew.work, sg_rq_end_io_usercontext);1411 schedule_work(&srp->ew.work);1412 }1413 return RQ_END_IO_NONE;1414}1415 1416static const struct file_operations sg_fops = {1417 .owner = THIS_MODULE,1418 .read = sg_read,1419 .write = sg_write,1420 .poll = sg_poll,1421 .unlocked_ioctl = sg_ioctl,1422 .compat_ioctl = compat_ptr_ioctl,1423 .open = sg_open,1424 .mmap = sg_mmap,1425 .release = sg_release,1426 .fasync = sg_fasync,1427};1428 1429static const struct class sg_sysfs_class = {1430 .name = "scsi_generic"1431};1432 1433static int sg_sysfs_valid = 0;1434 1435static Sg_device *1436sg_alloc(struct scsi_device *scsidp)1437{1438 struct request_queue *q = scsidp->request_queue;1439 Sg_device *sdp;1440 unsigned long iflags;1441 int error;1442 u32 k;1443 1444 sdp = kzalloc(sizeof(Sg_device), GFP_KERNEL);1445 if (!sdp) {1446 sdev_printk(KERN_WARNING, scsidp, "%s: kmalloc Sg_device "1447 "failure\n", __func__);1448 return ERR_PTR(-ENOMEM);1449 }1450 1451 idr_preload(GFP_KERNEL);1452 write_lock_irqsave(&sg_index_lock, iflags);1453 1454 error = idr_alloc(&sg_index_idr, sdp, 0, SG_MAX_DEVS, GFP_NOWAIT);1455 if (error < 0) {1456 if (error == -ENOSPC) {1457 sdev_printk(KERN_WARNING, scsidp,1458 "Unable to attach sg device type=%d, minor number exceeds %d\n",1459 scsidp->type, SG_MAX_DEVS - 1);1460 error = -ENODEV;1461 } else {1462 sdev_printk(KERN_WARNING, scsidp, "%s: idr "1463 "allocation Sg_device failure: %d\n",1464 __func__, error);1465 }1466 goto out_unlock;1467 }1468 k = error;1469 1470 SCSI_LOG_TIMEOUT(3, sdev_printk(KERN_INFO, scsidp,1471 "sg_alloc: dev=%d \n", k));1472 sprintf(sdp->name, "sg%d", k);1473 sdp->device = scsidp;1474 mutex_init(&sdp->open_rel_lock);1475 INIT_LIST_HEAD(&sdp->sfds);1476 init_waitqueue_head(&sdp->open_wait);1477 atomic_set(&sdp->detaching, 0);1478 rwlock_init(&sdp->sfd_lock);1479 sdp->sg_tablesize = queue_max_segments(q);1480 sdp->index = k;1481 kref_init(&sdp->d_ref);1482 error = 0;1483 1484out_unlock:1485 write_unlock_irqrestore(&sg_index_lock, iflags);1486 idr_preload_end();1487 1488 if (error) {1489 kfree(sdp);1490 return ERR_PTR(error);1491 }1492 return sdp;1493}1494 1495static int1496sg_add_device(struct device *cl_dev)1497{1498 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);1499 Sg_device *sdp = NULL;1500 struct cdev * cdev = NULL;1501 int error;1502 unsigned long iflags;1503 1504 if (!blk_get_queue(scsidp->request_queue)) {1505 pr_warn("%s: get scsi_device queue failed\n", __func__);1506 return -ENODEV;1507 }1508 1509 error = -ENOMEM;1510 cdev = cdev_alloc();1511 if (!cdev) {1512 pr_warn("%s: cdev_alloc failed\n", __func__);1513 goto out;1514 }1515 cdev->owner = THIS_MODULE;1516 cdev->ops = &sg_fops;1517 1518 sdp = sg_alloc(scsidp);1519 if (IS_ERR(sdp)) {1520 pr_warn("%s: sg_alloc failed\n", __func__);1521 error = PTR_ERR(sdp);1522 goto out;1523 }1524 1525 error = cdev_add(cdev, MKDEV(SCSI_GENERIC_MAJOR, sdp->index), 1);1526 if (error)1527 goto cdev_add_err;1528 1529 sdp->cdev = cdev;1530 if (sg_sysfs_valid) {1531 struct device *sg_class_member;1532 1533 sg_class_member = device_create(&sg_sysfs_class, cl_dev->parent,1534 MKDEV(SCSI_GENERIC_MAJOR,1535 sdp->index),1536 sdp, "%s", sdp->name);1537 if (IS_ERR(sg_class_member)) {1538 pr_err("%s: device_create failed\n", __func__);1539 error = PTR_ERR(sg_class_member);1540 goto cdev_add_err;1541 }1542 error = sysfs_create_link(&scsidp->sdev_gendev.kobj,1543 &sg_class_member->kobj, "generic");1544 if (error)1545 pr_err("%s: unable to make symlink 'generic' back "1546 "to sg%d\n", __func__, sdp->index);1547 } else1548 pr_warn("%s: sg_sys Invalid\n", __func__);1549 1550 sdev_printk(KERN_NOTICE, scsidp, "Attached scsi generic sg%d "1551 "type %d\n", sdp->index, scsidp->type);1552 1553 dev_set_drvdata(cl_dev, sdp);1554 1555 return 0;1556 1557cdev_add_err:1558 write_lock_irqsave(&sg_index_lock, iflags);1559 idr_remove(&sg_index_idr, sdp->index);1560 write_unlock_irqrestore(&sg_index_lock, iflags);1561 kfree(sdp);1562 1563out:1564 if (cdev)1565 cdev_del(cdev);1566 blk_put_queue(scsidp->request_queue);1567 return error;1568}1569 1570static void1571sg_device_destroy(struct kref *kref)1572{1573 struct sg_device *sdp = container_of(kref, struct sg_device, d_ref);1574 struct request_queue *q = sdp->device->request_queue;1575 unsigned long flags;1576 1577 /* CAUTION! Note that the device can still be found via idr_find()1578 * even though the refcount is 0. Therefore, do idr_remove() BEFORE1579 * any other cleanup.1580 */1581 1582 blk_trace_remove(q);1583 blk_put_queue(q);1584 1585 write_lock_irqsave(&sg_index_lock, flags);1586 idr_remove(&sg_index_idr, sdp->index);1587 write_unlock_irqrestore(&sg_index_lock, flags);1588 1589 SCSI_LOG_TIMEOUT(3,1590 sg_printk(KERN_INFO, sdp, "sg_device_destroy\n"));1591 1592 kfree(sdp);1593}1594 1595static void1596sg_remove_device(struct device *cl_dev)1597{1598 struct scsi_device *scsidp = to_scsi_device(cl_dev->parent);1599 Sg_device *sdp = dev_get_drvdata(cl_dev);1600 unsigned long iflags;1601 Sg_fd *sfp;1602 int val;1603 1604 if (!sdp)1605 return;1606 /* want sdp->detaching non-zero as soon as possible */1607 val = atomic_inc_return(&sdp->detaching);1608 if (val > 1)1609 return; /* only want to do following once per device */1610 1611 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,1612 "%s\n", __func__));1613 1614 read_lock_irqsave(&sdp->sfd_lock, iflags);1615 list_for_each_entry(sfp, &sdp->sfds, sfd_siblings) {1616 wake_up_interruptible_all(&sfp->read_wait);1617 kill_fasync(&sfp->async_qp, SIGPOLL, POLL_HUP);1618 }1619 wake_up_interruptible_all(&sdp->open_wait);1620 read_unlock_irqrestore(&sdp->sfd_lock, iflags);1621 1622 sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");1623 device_destroy(&sg_sysfs_class, MKDEV(SCSI_GENERIC_MAJOR, sdp->index));1624 cdev_del(sdp->cdev);1625 sdp->cdev = NULL;1626 1627 kref_put(&sdp->d_ref, sg_device_destroy);1628}1629 1630module_param_named(scatter_elem_sz, scatter_elem_sz, int, S_IRUGO | S_IWUSR);1631module_param_named(def_reserved_size, def_reserved_size, int,1632 S_IRUGO | S_IWUSR);1633module_param_named(allow_dio, sg_allow_dio, int, S_IRUGO | S_IWUSR);1634 1635MODULE_AUTHOR("Douglas Gilbert");1636MODULE_DESCRIPTION("SCSI generic (sg) driver");1637MODULE_LICENSE("GPL");1638MODULE_VERSION(SG_VERSION_STR);1639MODULE_ALIAS_CHARDEV_MAJOR(SCSI_GENERIC_MAJOR);1640 1641MODULE_PARM_DESC(scatter_elem_sz, "scatter gather element "1642 "size (default: max(SG_SCATTER_SZ, PAGE_SIZE))");1643MODULE_PARM_DESC(def_reserved_size, "size of buffer reserved for each fd");1644MODULE_PARM_DESC(allow_dio, "allow direct I/O (default: 0 (disallow))");1645 1646#ifdef CONFIG_SYSCTL1647#include <linux/sysctl.h>1648 1649static struct ctl_table sg_sysctls[] = {1650 {1651 .procname = "sg-big-buff",1652 .data = &sg_big_buff,1653 .maxlen = sizeof(int),1654 .mode = 0444,1655 .proc_handler = proc_dointvec,1656 },1657};1658 1659static struct ctl_table_header *hdr;1660static void register_sg_sysctls(void)1661{1662 if (!hdr)1663 hdr = register_sysctl("kernel", sg_sysctls);1664}1665 1666static void unregister_sg_sysctls(void)1667{1668 if (hdr)1669 unregister_sysctl_table(hdr);1670}1671#else1672#define register_sg_sysctls() do { } while (0)1673#define unregister_sg_sysctls() do { } while (0)1674#endif /* CONFIG_SYSCTL */1675 1676static int __init1677init_sg(void)1678{1679 int rc;1680 1681 if (scatter_elem_sz < PAGE_SIZE) {1682 scatter_elem_sz = PAGE_SIZE;1683 scatter_elem_sz_prev = scatter_elem_sz;1684 }1685 if (def_reserved_size >= 0)1686 sg_big_buff = def_reserved_size;1687 else1688 def_reserved_size = sg_big_buff;1689 1690 rc = register_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), 1691 SG_MAX_DEVS, "sg");1692 if (rc)1693 return rc;1694 rc = class_register(&sg_sysfs_class);1695 if (rc)1696 goto err_out;1697 sg_sysfs_valid = 1;1698 rc = scsi_register_interface(&sg_interface);1699 if (0 == rc) {1700#ifdef CONFIG_SCSI_PROC_FS1701 sg_proc_init();1702#endif /* CONFIG_SCSI_PROC_FS */1703 return 0;1704 }1705 class_unregister(&sg_sysfs_class);1706 register_sg_sysctls();1707err_out:1708 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0), SG_MAX_DEVS);1709 return rc;1710}1711 1712static void __exit1713exit_sg(void)1714{1715 unregister_sg_sysctls();1716#ifdef CONFIG_SCSI_PROC_FS1717 remove_proc_subtree("scsi/sg", NULL);1718#endif /* CONFIG_SCSI_PROC_FS */1719 scsi_unregister_interface(&sg_interface);1720 class_unregister(&sg_sysfs_class);1721 sg_sysfs_valid = 0;1722 unregister_chrdev_region(MKDEV(SCSI_GENERIC_MAJOR, 0),1723 SG_MAX_DEVS);1724 idr_destroy(&sg_index_idr);1725}1726 1727static int1728sg_start_req(Sg_request *srp, unsigned char *cmd)1729{1730 int res;1731 struct request *rq;1732 Sg_fd *sfp = srp->parentfp;1733 sg_io_hdr_t *hp = &srp->header;1734 int dxfer_len = (int) hp->dxfer_len;1735 int dxfer_dir = hp->dxfer_direction;1736 unsigned int iov_count = hp->iovec_count;1737 Sg_scatter_hold *req_schp = &srp->data;1738 Sg_scatter_hold *rsv_schp = &sfp->reserve;1739 struct request_queue *q = sfp->parentdp->device->request_queue;1740 struct rq_map_data *md, map_data;1741 int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? ITER_SOURCE : ITER_DEST;1742 struct scsi_cmnd *scmd;1743 1744 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,1745 "sg_start_req: dxfer_len=%d\n",1746 dxfer_len));1747 1748 /*1749 * NOTE1750 *1751 * With scsi-mq enabled, there are a fixed number of preallocated1752 * requests equal in number to shost->can_queue. If all of the1753 * preallocated requests are already in use, then scsi_alloc_request()1754 * will sleep until an active command completes, freeing up a request.1755 * Although waiting in an asynchronous interface is less than ideal, we1756 * do not want to use BLK_MQ_REQ_NOWAIT here because userspace might1757 * not expect an EWOULDBLOCK from this condition.1758 */1759 rq = scsi_alloc_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ?1760 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);1761 if (IS_ERR(rq))1762 return PTR_ERR(rq);1763 scmd = blk_mq_rq_to_pdu(rq);1764 1765 if (hp->cmd_len > sizeof(scmd->cmnd)) {1766 blk_mq_free_request(rq);1767 return -EINVAL;1768 }1769 1770 memcpy(scmd->cmnd, cmd, hp->cmd_len);1771 scmd->cmd_len = hp->cmd_len;1772 1773 srp->rq = rq;1774 rq->end_io_data = srp;1775 scmd->allowed = SG_DEFAULT_RETRIES;1776 1777 if ((dxfer_len <= 0) || (dxfer_dir == SG_DXFER_NONE))1778 return 0;1779 1780 if (sg_allow_dio && hp->flags & SG_FLAG_DIRECT_IO &&1781 dxfer_dir != SG_DXFER_UNKNOWN && !iov_count &&1782 blk_rq_aligned(q, (unsigned long)hp->dxferp, dxfer_len))1783 md = NULL;1784 else1785 md = &map_data;1786 1787 if (md) {1788 mutex_lock(&sfp->f_mutex);1789 if (dxfer_len <= rsv_schp->bufflen &&1790 !sfp->res_in_use) {1791 sfp->res_in_use = 1;1792 sg_link_reserve(sfp, srp, dxfer_len);1793 } else if (hp->flags & SG_FLAG_MMAP_IO) {1794 res = -EBUSY; /* sfp->res_in_use == 1 */1795 if (dxfer_len > rsv_schp->bufflen)1796 res = -ENOMEM;1797 mutex_unlock(&sfp->f_mutex);1798 return res;1799 } else {1800 res = sg_build_indirect(req_schp, sfp, dxfer_len);1801 if (res) {1802 mutex_unlock(&sfp->f_mutex);1803 return res;1804 }1805 }1806 mutex_unlock(&sfp->f_mutex);1807 1808 md->pages = req_schp->pages;1809 md->page_order = req_schp->page_order;1810 md->nr_entries = req_schp->k_use_sg;1811 md->offset = 0;1812 md->null_mapped = hp->dxferp ? 0 : 1;1813 if (dxfer_dir == SG_DXFER_TO_FROM_DEV)1814 md->from_user = 1;1815 else1816 md->from_user = 0;1817 }1818 1819 res = blk_rq_map_user_io(rq, md, hp->dxferp, hp->dxfer_len,1820 GFP_ATOMIC, iov_count, iov_count, 1, rw);1821 if (!res) {1822 srp->bio = rq->bio;1823 1824 if (!md) {1825 req_schp->dio_in_use = 1;1826 hp->info |= SG_INFO_DIRECT_IO;1827 }1828 }1829 return res;1830}1831 1832static int1833sg_finish_rem_req(Sg_request *srp)1834{1835 int ret = 0;1836 1837 Sg_fd *sfp = srp->parentfp;1838 Sg_scatter_hold *req_schp = &srp->data;1839 1840 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,1841 "sg_finish_rem_req: res_used=%d\n",1842 (int) srp->res_used));1843 if (srp->bio)1844 ret = blk_rq_unmap_user(srp->bio);1845 1846 if (srp->rq)1847 blk_mq_free_request(srp->rq);1848 1849 if (srp->res_used)1850 sg_unlink_reserve(sfp, srp);1851 else1852 sg_remove_scat(sfp, req_schp);1853 1854 return ret;1855}1856 1857static int1858sg_build_sgat(Sg_scatter_hold * schp, const Sg_fd * sfp, int tablesize)1859{1860 int sg_bufflen = tablesize * sizeof(struct page *);1861 gfp_t gfp_flags = GFP_ATOMIC | __GFP_NOWARN;1862 1863 schp->pages = kzalloc(sg_bufflen, gfp_flags);1864 if (!schp->pages)1865 return -ENOMEM;1866 schp->sglist_len = sg_bufflen;1867 return tablesize; /* number of scat_gath elements allocated */1868}1869 1870static int1871sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)1872{1873 int ret_sz = 0, i, k, rem_sz, num, mx_sc_elems;1874 int sg_tablesize = sfp->parentdp->sg_tablesize;1875 int blk_size = buff_size, order;1876 gfp_t gfp_mask = GFP_ATOMIC | __GFP_COMP | __GFP_NOWARN | __GFP_ZERO;1877 1878 if (blk_size < 0)1879 return -EFAULT;1880 if (0 == blk_size)1881 ++blk_size; /* don't know why */1882 /* round request up to next highest SG_SECTOR_SZ byte boundary */1883 blk_size = ALIGN(blk_size, SG_SECTOR_SZ);1884 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,1885 "sg_build_indirect: buff_size=%d, blk_size=%d\n",1886 buff_size, blk_size));1887 1888 /* N.B. ret_sz carried into this block ... */1889 mx_sc_elems = sg_build_sgat(schp, sfp, sg_tablesize);1890 if (mx_sc_elems < 0)1891 return mx_sc_elems; /* most likely -ENOMEM */1892 1893 num = scatter_elem_sz;1894 if (unlikely(num != scatter_elem_sz_prev)) {1895 if (num < PAGE_SIZE) {1896 scatter_elem_sz = PAGE_SIZE;1897 scatter_elem_sz_prev = PAGE_SIZE;1898 } else1899 scatter_elem_sz_prev = num;1900 }1901 1902 order = get_order(num);1903retry:1904 ret_sz = 1 << (PAGE_SHIFT + order);1905 1906 for (k = 0, rem_sz = blk_size; rem_sz > 0 && k < mx_sc_elems;1907 k++, rem_sz -= ret_sz) {1908 1909 num = (rem_sz > scatter_elem_sz_prev) ?1910 scatter_elem_sz_prev : rem_sz;1911 1912 schp->pages[k] = alloc_pages(gfp_mask, order);1913 if (!schp->pages[k])1914 goto out;1915 1916 if (num == scatter_elem_sz_prev) {1917 if (unlikely(ret_sz > scatter_elem_sz_prev)) {1918 scatter_elem_sz = ret_sz;1919 scatter_elem_sz_prev = ret_sz;1920 }1921 }1922 1923 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,1924 "sg_build_indirect: k=%d, num=%d, ret_sz=%d\n",1925 k, num, ret_sz));1926 } /* end of for loop */1927 1928 schp->page_order = order;1929 schp->k_use_sg = k;1930 SCSI_LOG_TIMEOUT(5, sg_printk(KERN_INFO, sfp->parentdp,1931 "sg_build_indirect: k_use_sg=%d, rem_sz=%d\n",1932 k, rem_sz));1933 1934 schp->bufflen = blk_size;1935 if (rem_sz > 0) /* must have failed */1936 return -ENOMEM;1937 return 0;1938out:1939 for (i = 0; i < k; i++)1940 __free_pages(schp->pages[i], order);1941 1942 if (--order >= 0)1943 goto retry;1944 1945 return -ENOMEM;1946}1947 1948static void1949sg_remove_scat(Sg_fd * sfp, Sg_scatter_hold * schp)1950{1951 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,1952 "sg_remove_scat: k_use_sg=%d\n", schp->k_use_sg));1953 if (schp->pages && schp->sglist_len > 0) {1954 if (!schp->dio_in_use) {1955 int k;1956 1957 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {1958 SCSI_LOG_TIMEOUT(5,1959 sg_printk(KERN_INFO, sfp->parentdp,1960 "sg_remove_scat: k=%d, pg=0x%p\n",1961 k, schp->pages[k]));1962 __free_pages(schp->pages[k], schp->page_order);1963 }1964 1965 kfree(schp->pages);1966 }1967 }1968 memset(schp, 0, sizeof (*schp));1969}1970 1971static int1972sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)1973{1974 Sg_scatter_hold *schp = &srp->data;1975 int k, num;1976 1977 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,1978 "sg_read_oxfer: num_read_xfer=%d\n",1979 num_read_xfer));1980 if ((!outp) || (num_read_xfer <= 0))1981 return 0;1982 1983 num = 1 << (PAGE_SHIFT + schp->page_order);1984 for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) {1985 if (num > num_read_xfer) {1986 if (copy_to_user(outp, page_address(schp->pages[k]),1987 num_read_xfer))1988 return -EFAULT;1989 break;1990 } else {1991 if (copy_to_user(outp, page_address(schp->pages[k]),1992 num))1993 return -EFAULT;1994 num_read_xfer -= num;1995 if (num_read_xfer <= 0)1996 break;1997 outp += num;1998 }1999 }2000 2001 return 0;2002}2003 2004static void2005sg_build_reserve(Sg_fd * sfp, int req_size)2006{2007 Sg_scatter_hold *schp = &sfp->reserve;2008 2009 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,2010 "sg_build_reserve: req_size=%d\n", req_size));2011 do {2012 if (req_size < PAGE_SIZE)2013 req_size = PAGE_SIZE;2014 if (0 == sg_build_indirect(schp, sfp, req_size))2015 return;2016 else2017 sg_remove_scat(sfp, schp);2018 req_size >>= 1; /* divide by 2 */2019 } while (req_size > (PAGE_SIZE / 2));2020}2021 2022static void2023sg_link_reserve(Sg_fd * sfp, Sg_request * srp, int size)2024{2025 Sg_scatter_hold *req_schp = &srp->data;2026 Sg_scatter_hold *rsv_schp = &sfp->reserve;2027 int k, num, rem;2028 2029 srp->res_used = 1;2030 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp,2031 "sg_link_reserve: size=%d\n", size));2032 rem = size;2033 2034 num = 1 << (PAGE_SHIFT + rsv_schp->page_order);2035 for (k = 0; k < rsv_schp->k_use_sg; k++) {2036 if (rem <= num) {2037 req_schp->k_use_sg = k + 1;2038 req_schp->sglist_len = rsv_schp->sglist_len;2039 req_schp->pages = rsv_schp->pages;2040 2041 req_schp->bufflen = size;2042 req_schp->page_order = rsv_schp->page_order;2043 break;2044 } else2045 rem -= num;2046 }2047 2048 if (k >= rsv_schp->k_use_sg)2049 SCSI_LOG_TIMEOUT(1, sg_printk(KERN_INFO, sfp->parentdp,2050 "sg_link_reserve: BAD size\n"));2051}2052 2053static void2054sg_unlink_reserve(Sg_fd * sfp, Sg_request * srp)2055{2056 Sg_scatter_hold *req_schp = &srp->data;2057 2058 SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, srp->parentfp->parentdp,2059 "sg_unlink_reserve: req->k_use_sg=%d\n",2060 (int) req_schp->k_use_sg));2061 req_schp->k_use_sg = 0;2062 req_schp->bufflen = 0;2063 req_schp->pages = NULL;2064 req_schp->page_order = 0;2065 req_schp->sglist_len = 0;2066 srp->res_used = 0;2067 /* Called without mutex lock to avoid deadlock */2068 sfp->res_in_use = 0;2069}2070 2071static Sg_request *2072sg_get_rq_mark(Sg_fd * sfp, int pack_id, bool *busy)2073{2074 Sg_request *resp;2075 unsigned long iflags;2076 2077 *busy = false;2078 write_lock_irqsave(&sfp->rq_list_lock, iflags);2079 list_for_each_entry(resp, &sfp->rq_list, entry) {2080 /* look for requests that are not SG_IO owned */2081 if ((!resp->sg_io_owned) &&2082 ((-1 == pack_id) || (resp->header.pack_id == pack_id))) {2083 switch (resp->done) {2084 case 0: /* request active */2085 *busy = true;2086 break;2087 case 1: /* request done; response ready to return */2088 resp->done = 2; /* guard against other readers */2089 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);2090 return resp;2091 case 2: /* response already being returned */2092 break;2093 }2094 }2095 }2096 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);2097 return NULL;2098}2099 2100/* always adds to end of list */2101static Sg_request *2102sg_add_request(Sg_fd * sfp)2103{2104 int k;2105 unsigned long iflags;2106 Sg_request *rp = sfp->req_arr;2107 2108 write_lock_irqsave(&sfp->rq_list_lock, iflags);2109 if (!list_empty(&sfp->rq_list)) {2110 if (!sfp->cmd_q)2111 goto out_unlock;2112 2113 for (k = 0; k < SG_MAX_QUEUE; ++k, ++rp) {2114 if (!rp->parentfp)2115 break;2116 }2117 if (k >= SG_MAX_QUEUE)2118 goto out_unlock;2119 }2120 memset(rp, 0, sizeof (Sg_request));2121 rp->parentfp = sfp;2122 rp->header.duration = jiffies_to_msecs(jiffies);2123 list_add_tail(&rp->entry, &sfp->rq_list);2124 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);2125 return rp;2126out_unlock:2127 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);2128 return NULL;2129}2130 2131/* Return of 1 for found; 0 for not found */2132static int2133sg_remove_request(Sg_fd * sfp, Sg_request * srp)2134{2135 unsigned long iflags;2136 int res = 0;2137 2138 if (!sfp || !srp || list_empty(&sfp->rq_list))2139 return res;2140 write_lock_irqsave(&sfp->rq_list_lock, iflags);2141 if (!list_empty(&srp->entry)) {2142 list_del(&srp->entry);2143 srp->parentfp = NULL;2144 res = 1;2145 }2146 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);2147 2148 /*2149 * If the device is detaching, wakeup any readers in case we just2150 * removed the last response, which would leave nothing for them to2151 * return other than -ENODEV.2152 */2153 if (unlikely(atomic_read(&sfp->parentdp->detaching)))2154 wake_up_interruptible_all(&sfp->read_wait);2155 2156 return res;2157}2158 2159static Sg_fd *2160sg_add_sfp(Sg_device * sdp)2161{2162 Sg_fd *sfp;2163 unsigned long iflags;2164 int bufflen;2165 2166 sfp = kzalloc(sizeof(*sfp), GFP_ATOMIC | __GFP_NOWARN);2167 if (!sfp)2168 return ERR_PTR(-ENOMEM);2169 2170 init_waitqueue_head(&sfp->read_wait);2171 rwlock_init(&sfp->rq_list_lock);2172 INIT_LIST_HEAD(&sfp->rq_list);2173 kref_init(&sfp->f_ref);2174 mutex_init(&sfp->f_mutex);2175 sfp->timeout = SG_DEFAULT_TIMEOUT;2176 sfp->timeout_user = SG_DEFAULT_TIMEOUT_USER;2177 sfp->force_packid = SG_DEF_FORCE_PACK_ID;2178 sfp->cmd_q = SG_DEF_COMMAND_Q;2179 sfp->keep_orphan = SG_DEF_KEEP_ORPHAN;2180 sfp->parentdp = sdp;2181 write_lock_irqsave(&sdp->sfd_lock, iflags);2182 if (atomic_read(&sdp->detaching)) {2183 write_unlock_irqrestore(&sdp->sfd_lock, iflags);2184 kfree(sfp);2185 return ERR_PTR(-ENODEV);2186 }2187 list_add_tail(&sfp->sfd_siblings, &sdp->sfds);2188 write_unlock_irqrestore(&sdp->sfd_lock, iflags);2189 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,2190 "sg_add_sfp: sfp=0x%p\n", sfp));2191 if (unlikely(sg_big_buff != def_reserved_size))2192 sg_big_buff = def_reserved_size;2193 2194 bufflen = min_t(int, sg_big_buff,2195 max_sectors_bytes(sdp->device->request_queue));2196 sg_build_reserve(sfp, bufflen);2197 SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp,2198 "sg_add_sfp: bufflen=%d, k_use_sg=%d\n",2199 sfp->reserve.bufflen,2200 sfp->reserve.k_use_sg));2201 2202 kref_get(&sdp->d_ref);2203 __module_get(THIS_MODULE);2204 return sfp;2205}2206 2207static void2208sg_remove_sfp_usercontext(struct work_struct *work)2209{2210 struct sg_fd *sfp = container_of(work, struct sg_fd, ew.work);2211 struct sg_device *sdp = sfp->parentdp;2212 struct scsi_device *device = sdp->device;2213 Sg_request *srp;2214 unsigned long iflags;2215 2216 /* Cleanup any responses which were never read(). */2217 write_lock_irqsave(&sfp->rq_list_lock, iflags);2218 while (!list_empty(&sfp->rq_list)) {2219 srp = list_first_entry(&sfp->rq_list, Sg_request, entry);2220 sg_finish_rem_req(srp);2221 list_del(&srp->entry);2222 srp->parentfp = NULL;2223 }2224 write_unlock_irqrestore(&sfp->rq_list_lock, iflags);2225 2226 if (sfp->reserve.bufflen > 0) {2227 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,2228 "sg_remove_sfp: bufflen=%d, k_use_sg=%d\n",2229 (int) sfp->reserve.bufflen,2230 (int) sfp->reserve.k_use_sg));2231 sg_remove_scat(sfp, &sfp->reserve);2232 }2233 2234 SCSI_LOG_TIMEOUT(6, sg_printk(KERN_INFO, sdp,2235 "sg_remove_sfp: sfp=0x%p\n", sfp));2236 kfree(sfp);2237 2238 kref_put(&sdp->d_ref, sg_device_destroy);2239 scsi_device_put(device);2240 module_put(THIS_MODULE);2241}2242 2243static void2244sg_remove_sfp(struct kref *kref)2245{2246 struct sg_fd *sfp = container_of(kref, struct sg_fd, f_ref);2247 struct sg_device *sdp = sfp->parentdp;2248 unsigned long iflags;2249 2250 write_lock_irqsave(&sdp->sfd_lock, iflags);2251 list_del(&sfp->sfd_siblings);2252 write_unlock_irqrestore(&sdp->sfd_lock, iflags);2253 2254 INIT_WORK(&sfp->ew.work, sg_remove_sfp_usercontext);2255 schedule_work(&sfp->ew.work);2256}2257 2258#ifdef CONFIG_SCSI_PROC_FS2259static int2260sg_idr_max_id(int id, void *p, void *data)2261{2262 int *k = data;2263 2264 if (*k < id)2265 *k = id;2266 2267 return 0;2268}2269 2270static int2271sg_last_dev(void)2272{2273 int k = -1;2274 unsigned long iflags;2275 2276 read_lock_irqsave(&sg_index_lock, iflags);2277 idr_for_each(&sg_index_idr, sg_idr_max_id, &k);2278 read_unlock_irqrestore(&sg_index_lock, iflags);2279 return k + 1; /* origin 1 */2280}2281#endif2282 2283/* must be called with sg_index_lock held */2284static Sg_device *sg_lookup_dev(int dev)2285{2286 return idr_find(&sg_index_idr, dev);2287}2288 2289static Sg_device *2290sg_get_dev(int dev)2291{2292 struct sg_device *sdp;2293 unsigned long flags;2294 2295 read_lock_irqsave(&sg_index_lock, flags);2296 sdp = sg_lookup_dev(dev);2297 if (!sdp)2298 sdp = ERR_PTR(-ENXIO);2299 else if (atomic_read(&sdp->detaching)) {2300 /* If sdp->detaching, then the refcount may already be 0, in2301 * which case it would be a bug to do kref_get().2302 */2303 sdp = ERR_PTR(-ENODEV);2304 } else2305 kref_get(&sdp->d_ref);2306 read_unlock_irqrestore(&sg_index_lock, flags);2307 2308 return sdp;2309}2310 2311#ifdef CONFIG_SCSI_PROC_FS2312static int sg_proc_seq_show_int(struct seq_file *s, void *v);2313 2314static int sg_proc_single_open_adio(struct inode *inode, struct file *file);2315static ssize_t sg_proc_write_adio(struct file *filp, const char __user *buffer,2316 size_t count, loff_t *off);2317static const struct proc_ops adio_proc_ops = {2318 .proc_open = sg_proc_single_open_adio,2319 .proc_read = seq_read,2320 .proc_lseek = seq_lseek,2321 .proc_write = sg_proc_write_adio,2322 .proc_release = single_release,2323};2324 2325static int sg_proc_single_open_dressz(struct inode *inode, struct file *file);2326static ssize_t sg_proc_write_dressz(struct file *filp, 2327 const char __user *buffer, size_t count, loff_t *off);2328static const struct proc_ops dressz_proc_ops = {2329 .proc_open = sg_proc_single_open_dressz,2330 .proc_read = seq_read,2331 .proc_lseek = seq_lseek,2332 .proc_write = sg_proc_write_dressz,2333 .proc_release = single_release,2334};2335 2336static int sg_proc_seq_show_version(struct seq_file *s, void *v);2337static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v);2338static int sg_proc_seq_show_dev(struct seq_file *s, void *v);2339static void * dev_seq_start(struct seq_file *s, loff_t *pos);2340static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos);2341static void dev_seq_stop(struct seq_file *s, void *v);2342static const struct seq_operations dev_seq_ops = {2343 .start = dev_seq_start,2344 .next = dev_seq_next,2345 .stop = dev_seq_stop,2346 .show = sg_proc_seq_show_dev,2347};2348 2349static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v);2350static const struct seq_operations devstrs_seq_ops = {2351 .start = dev_seq_start,2352 .next = dev_seq_next,2353 .stop = dev_seq_stop,2354 .show = sg_proc_seq_show_devstrs,2355};2356 2357static int sg_proc_seq_show_debug(struct seq_file *s, void *v);2358static const struct seq_operations debug_seq_ops = {2359 .start = dev_seq_start,2360 .next = dev_seq_next,2361 .stop = dev_seq_stop,2362 .show = sg_proc_seq_show_debug,2363};2364 2365static int2366sg_proc_init(void)2367{2368 struct proc_dir_entry *p;2369 2370 p = proc_mkdir("scsi/sg", NULL);2371 if (!p)2372 return 1;2373 2374 proc_create("allow_dio", S_IRUGO | S_IWUSR, p, &adio_proc_ops);2375 proc_create_seq("debug", S_IRUGO, p, &debug_seq_ops);2376 proc_create("def_reserved_size", S_IRUGO | S_IWUSR, p, &dressz_proc_ops);2377 proc_create_single("device_hdr", S_IRUGO, p, sg_proc_seq_show_devhdr);2378 proc_create_seq("devices", S_IRUGO, p, &dev_seq_ops);2379 proc_create_seq("device_strs", S_IRUGO, p, &devstrs_seq_ops);2380 proc_create_single("version", S_IRUGO, p, sg_proc_seq_show_version);2381 return 0;2382}2383 2384 2385static int sg_proc_seq_show_int(struct seq_file *s, void *v)2386{2387 seq_printf(s, "%d\n", *((int *)s->private));2388 return 0;2389}2390 2391static int sg_proc_single_open_adio(struct inode *inode, struct file *file)2392{2393 return single_open(file, sg_proc_seq_show_int, &sg_allow_dio);2394}2395 2396static ssize_t 2397sg_proc_write_adio(struct file *filp, const char __user *buffer,2398 size_t count, loff_t *off)2399{2400 int err;2401 unsigned long num;2402 2403 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))2404 return -EACCES;2405 err = kstrtoul_from_user(buffer, count, 0, &num);2406 if (err)2407 return err;2408 sg_allow_dio = num ? 1 : 0;2409 return count;2410}2411 2412static int sg_proc_single_open_dressz(struct inode *inode, struct file *file)2413{2414 return single_open(file, sg_proc_seq_show_int, &sg_big_buff);2415}2416 2417static ssize_t 2418sg_proc_write_dressz(struct file *filp, const char __user *buffer,2419 size_t count, loff_t *off)2420{2421 int err;2422 unsigned long k = ULONG_MAX;2423 2424 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))2425 return -EACCES;2426 2427 err = kstrtoul_from_user(buffer, count, 0, &k);2428 if (err)2429 return err;2430 if (k <= 1048576) { /* limit "big buff" to 1 MB */2431 sg_big_buff = k;2432 return count;2433 }2434 return -ERANGE;2435}2436 2437static int sg_proc_seq_show_version(struct seq_file *s, void *v)2438{2439 seq_printf(s, "%d\t%s [%s]\n", sg_version_num, SG_VERSION_STR,2440 sg_version_date);2441 return 0;2442}2443 2444static int sg_proc_seq_show_devhdr(struct seq_file *s, void *v)2445{2446 seq_puts(s, "host\tchan\tid\tlun\ttype\topens\tqdepth\tbusy\tonline\n");2447 return 0;2448}2449 2450struct sg_proc_deviter {2451 loff_t index;2452 size_t max;2453};2454 2455static void * dev_seq_start(struct seq_file *s, loff_t *pos)2456{2457 struct sg_proc_deviter * it = kmalloc(sizeof(*it), GFP_KERNEL);2458 2459 s->private = it;2460 if (! it)2461 return NULL;2462 2463 it->index = *pos;2464 it->max = sg_last_dev();2465 if (it->index >= it->max)2466 return NULL;2467 return it;2468}2469 2470static void * dev_seq_next(struct seq_file *s, void *v, loff_t *pos)2471{2472 struct sg_proc_deviter * it = s->private;2473 2474 *pos = ++it->index;2475 return (it->index < it->max) ? it : NULL;2476}2477 2478static void dev_seq_stop(struct seq_file *s, void *v)2479{2480 kfree(s->private);2481}2482 2483static int sg_proc_seq_show_dev(struct seq_file *s, void *v)2484{2485 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;2486 Sg_device *sdp;2487 struct scsi_device *scsidp;2488 unsigned long iflags;2489 2490 read_lock_irqsave(&sg_index_lock, iflags);2491 sdp = it ? sg_lookup_dev(it->index) : NULL;2492 if ((NULL == sdp) || (NULL == sdp->device) ||2493 (atomic_read(&sdp->detaching)))2494 seq_puts(s, "-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\t-1\n");2495 else {2496 scsidp = sdp->device;2497 seq_printf(s, "%d\t%d\t%d\t%llu\t%d\t%d\t%d\t%d\t%d\n",2498 scsidp->host->host_no, scsidp->channel,2499 scsidp->id, scsidp->lun, (int) scsidp->type,2500 1,2501 (int) scsidp->queue_depth,2502 (int) scsi_device_busy(scsidp),2503 (int) scsi_device_online(scsidp));2504 }2505 read_unlock_irqrestore(&sg_index_lock, iflags);2506 return 0;2507}2508 2509static int sg_proc_seq_show_devstrs(struct seq_file *s, void *v)2510{2511 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;2512 Sg_device *sdp;2513 struct scsi_device *scsidp;2514 unsigned long iflags;2515 2516 read_lock_irqsave(&sg_index_lock, iflags);2517 sdp = it ? sg_lookup_dev(it->index) : NULL;2518 scsidp = sdp ? sdp->device : NULL;2519 if (sdp && scsidp && (!atomic_read(&sdp->detaching)))2520 seq_printf(s, "%8.8s\t%16.16s\t%4.4s\n",2521 scsidp->vendor, scsidp->model, scsidp->rev);2522 else2523 seq_puts(s, "<no active device>\n");2524 read_unlock_irqrestore(&sg_index_lock, iflags);2525 return 0;2526}2527 2528/* must be called while holding sg_index_lock */2529static void sg_proc_debug_helper(struct seq_file *s, Sg_device * sdp)2530{2531 int k, new_interface, blen, usg;2532 Sg_request *srp;2533 Sg_fd *fp;2534 const sg_io_hdr_t *hp;2535 const char * cp;2536 unsigned int ms;2537 2538 k = 0;2539 list_for_each_entry(fp, &sdp->sfds, sfd_siblings) {2540 k++;2541 read_lock(&fp->rq_list_lock); /* irqs already disabled */2542 seq_printf(s, " FD(%d): timeout=%dms bufflen=%d "2543 "(res)sgat=%d low_dma=%d\n", k,2544 jiffies_to_msecs(fp->timeout),2545 fp->reserve.bufflen,2546 (int) fp->reserve.k_use_sg, 0);2547 seq_printf(s, " cmd_q=%d f_packid=%d k_orphan=%d closed=0\n",2548 (int) fp->cmd_q, (int) fp->force_packid,2549 (int) fp->keep_orphan);2550 list_for_each_entry(srp, &fp->rq_list, entry) {2551 hp = &srp->header;2552 new_interface = (hp->interface_id == '\0') ? 0 : 1;2553 if (srp->res_used) {2554 if (new_interface &&2555 (SG_FLAG_MMAP_IO & hp->flags))2556 cp = " mmap>> ";2557 else2558 cp = " rb>> ";2559 } else {2560 if (SG_INFO_DIRECT_IO_MASK & hp->info)2561 cp = " dio>> ";2562 else2563 cp = " ";2564 }2565 seq_puts(s, cp);2566 blen = srp->data.bufflen;2567 usg = srp->data.k_use_sg;2568 seq_puts(s, srp->done ?2569 ((1 == srp->done) ? "rcv:" : "fin:")2570 : "act:");2571 seq_printf(s, " id=%d blen=%d",2572 srp->header.pack_id, blen);2573 if (srp->done)2574 seq_printf(s, " dur=%d", hp->duration);2575 else {2576 ms = jiffies_to_msecs(jiffies);2577 seq_printf(s, " t_o/elap=%d/%d",2578 (new_interface ? hp->timeout :2579 jiffies_to_msecs(fp->timeout)),2580 (ms > hp->duration ? ms - hp->duration : 0));2581 }2582 seq_printf(s, "ms sgat=%d op=0x%02x\n", usg,2583 (int) srp->data.cmd_opcode);2584 }2585 if (list_empty(&fp->rq_list))2586 seq_puts(s, " No requests active\n");2587 read_unlock(&fp->rq_list_lock);2588 }2589}2590 2591static int sg_proc_seq_show_debug(struct seq_file *s, void *v)2592{2593 struct sg_proc_deviter * it = (struct sg_proc_deviter *) v;2594 Sg_device *sdp;2595 unsigned long iflags;2596 2597 if (it && (0 == it->index))2598 seq_printf(s, "max_active_device=%d def_reserved_size=%d\n",2599 (int)it->max, sg_big_buff);2600 2601 read_lock_irqsave(&sg_index_lock, iflags);2602 sdp = it ? sg_lookup_dev(it->index) : NULL;2603 if (NULL == sdp)2604 goto skip;2605 read_lock(&sdp->sfd_lock);2606 if (!list_empty(&sdp->sfds)) {2607 seq_printf(s, " >>> device=%s ", sdp->name);2608 if (atomic_read(&sdp->detaching))2609 seq_puts(s, "detaching pending close ");2610 else if (sdp->device) {2611 struct scsi_device *scsidp = sdp->device;2612 2613 seq_printf(s, "%d:%d:%d:%llu em=%d",2614 scsidp->host->host_no,2615 scsidp->channel, scsidp->id,2616 scsidp->lun,2617 scsidp->host->hostt->emulated);2618 }2619 seq_printf(s, " sg_tablesize=%d excl=%d open_cnt=%d\n",2620 sdp->sg_tablesize, sdp->exclude, sdp->open_cnt);2621 sg_proc_debug_helper(s, sdp);2622 }2623 read_unlock(&sdp->sfd_lock);2624skip:2625 read_unlock_irqrestore(&sg_index_lock, iflags);2626 return 0;2627}2628 2629#endif /* CONFIG_SCSI_PROC_FS */2630 2631module_init(init_sg);2632module_exit(exit_sg);2633