11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * scsi.c Copyright (C) 1992 Drew Eckhardt 31da177e4SLinus Torvalds * Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale 41da177e4SLinus Torvalds * Copyright (C) 2002, 2003 Christoph Hellwig 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * generic mid-level SCSI driver 71da177e4SLinus Torvalds * Initial versions: Drew Eckhardt 81da177e4SLinus Torvalds * Subsequent revisions: Eric Youngdale 91da177e4SLinus Torvalds * 101da177e4SLinus Torvalds * <drew@colorado.edu> 111da177e4SLinus Torvalds * 121da177e4SLinus Torvalds * Bug correction thanks go to : 131da177e4SLinus Torvalds * Rik Faith <faith@cs.unc.edu> 141da177e4SLinus Torvalds * Tommy Thorn <tthorn> 151da177e4SLinus Torvalds * Thomas Wuensche <tw@fgb1.fgb.mw.tu-muenchen.de> 161da177e4SLinus Torvalds * 171da177e4SLinus Torvalds * Modified by Eric Youngdale eric@andante.org or ericy@gnu.ai.mit.edu to 181da177e4SLinus Torvalds * add scatter-gather, multiple outstanding request, and other 191da177e4SLinus Torvalds * enhancements. 201da177e4SLinus Torvalds * 211da177e4SLinus Torvalds * Native multichannel, wide scsi, /proc/scsi and hot plugging 221da177e4SLinus Torvalds * support added by Michael Neuffer <mike@i-connect.net> 231da177e4SLinus Torvalds * 241da177e4SLinus Torvalds * Added request_module("scsi_hostadapter") for kerneld: 251da177e4SLinus Torvalds * (Put an "alias scsi_hostadapter your_hostadapter" in /etc/modprobe.conf) 261da177e4SLinus Torvalds * Bjorn Ekwall <bj0rn@blox.se> 271da177e4SLinus Torvalds * (changed to kmod) 281da177e4SLinus Torvalds * 291da177e4SLinus Torvalds * Major improvements to the timeout, abort, and reset processing, 301da177e4SLinus Torvalds * as well as performance modifications for large queue depths by 311da177e4SLinus Torvalds * Leonard N. Zubkoff <lnz@dandelion.com> 321da177e4SLinus Torvalds * 331da177e4SLinus Torvalds * Converted cli() code to spinlocks, Ingo Molnar 341da177e4SLinus Torvalds * 351da177e4SLinus Torvalds * Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli 361da177e4SLinus Torvalds * 371da177e4SLinus Torvalds * out_of_space hacks, D. Gilbert (dpg) 990608 381da177e4SLinus Torvalds */ 391da177e4SLinus Torvalds 401da177e4SLinus Torvalds #include <linux/module.h> 411da177e4SLinus Torvalds #include <linux/moduleparam.h> 421da177e4SLinus Torvalds #include <linux/kernel.h> 431da177e4SLinus Torvalds #include <linux/timer.h> 441da177e4SLinus Torvalds #include <linux/string.h> 451da177e4SLinus Torvalds #include <linux/slab.h> 461da177e4SLinus Torvalds #include <linux/blkdev.h> 471da177e4SLinus Torvalds #include <linux/delay.h> 481da177e4SLinus Torvalds #include <linux/init.h> 491da177e4SLinus Torvalds #include <linux/completion.h> 501da177e4SLinus Torvalds #include <linux/unistd.h> 511da177e4SLinus Torvalds #include <linux/spinlock.h> 521da177e4SLinus Torvalds #include <linux/kmod.h> 531da177e4SLinus Torvalds #include <linux/interrupt.h> 541da177e4SLinus Torvalds #include <linux/notifier.h> 551da177e4SLinus Torvalds #include <linux/cpu.h> 560b950672SArjan van de Ven #include <linux/mutex.h> 572955b47dSDan Williams #include <linux/async.h> 583c6bdaeaSMartin K. Petersen #include <asm/unaligned.h> 591da177e4SLinus Torvalds 601da177e4SLinus Torvalds #include <scsi/scsi.h> 611da177e4SLinus Torvalds #include <scsi/scsi_cmnd.h> 621da177e4SLinus Torvalds #include <scsi/scsi_dbg.h> 631da177e4SLinus Torvalds #include <scsi/scsi_device.h> 647b3d9545SLinus Torvalds #include <scsi/scsi_driver.h> 651da177e4SLinus Torvalds #include <scsi/scsi_eh.h> 661da177e4SLinus Torvalds #include <scsi/scsi_host.h> 671da177e4SLinus Torvalds #include <scsi/scsi_tcq.h> 681da177e4SLinus Torvalds 691da177e4SLinus Torvalds #include "scsi_priv.h" 701da177e4SLinus Torvalds #include "scsi_logging.h" 711da177e4SLinus Torvalds 72bf816235SKei Tokunaga #define CREATE_TRACE_POINTS 73bf816235SKei Tokunaga #include <trace/events/scsi.h> 74bf816235SKei Tokunaga 751da177e4SLinus Torvalds /* 761da177e4SLinus Torvalds * Definitions and constants. 771da177e4SLinus Torvalds */ 781da177e4SLinus Torvalds 791da177e4SLinus Torvalds /* 801da177e4SLinus Torvalds * Note - the initial logging level can be set here to log events at boot time. 811da177e4SLinus Torvalds * After the system is up, you may enable logging via the /proc interface. 821da177e4SLinus Torvalds */ 831da177e4SLinus Torvalds unsigned int scsi_logging_level; 841da177e4SLinus Torvalds #if defined(CONFIG_SCSI_LOGGING) 851da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_logging_level); 861da177e4SLinus Torvalds #endif 871da177e4SLinus Torvalds 88ea80dadeSJames Bottomley /* sd, scsi core and power management need to coordinate flushing async actions */ 892955b47dSDan Williams ASYNC_DOMAIN(scsi_sd_probe_domain); 90a7a20d10SDan Williams EXPORT_SYMBOL(scsi_sd_probe_domain); 91a7a20d10SDan Williams 923c31b52fSDan Williams /* 933c31b52fSDan Williams * Separate domain (from scsi_sd_probe_domain) to maximize the benefit of 943c31b52fSDan Williams * asynchronous system resume operations. It is marked 'exclusive' to avoid 953c31b52fSDan Williams * being included in the async_synchronize_full() that is invoked by 963c31b52fSDan Williams * dpm_resume() 973c31b52fSDan Williams */ 983c31b52fSDan Williams ASYNC_DOMAIN_EXCLUSIVE(scsi_sd_pm_domain); 993c31b52fSDan Williams EXPORT_SYMBOL(scsi_sd_pm_domain); 1003c31b52fSDan Williams 101eb44820cSRob Landley /** 102eb44820cSRob Landley * scsi_put_command - Free a scsi command block 103eb44820cSRob Landley * @cmd: command block to free 1041da177e4SLinus Torvalds * 1051da177e4SLinus Torvalds * Returns: Nothing. 1061da177e4SLinus Torvalds * 1071da177e4SLinus Torvalds * Notes: The command must not belong to any lists. 1081da177e4SLinus Torvalds */ 1091da177e4SLinus Torvalds void scsi_put_command(struct scsi_cmnd *cmd) 1101da177e4SLinus Torvalds { 1112dd6fb59SBart Van Assche scsi_del_cmd_from_list(cmd); 112fcc95a76SBart Van Assche BUG_ON(delayed_work_pending(&cmd->abort_work)); 113de25deb1SFUJITA Tomonori } 114de25deb1SFUJITA Tomonori 1151da177e4SLinus Torvalds #ifdef CONFIG_SCSI_LOGGING 1161da177e4SLinus Torvalds void scsi_log_send(struct scsi_cmnd *cmd) 1171da177e4SLinus Torvalds { 1181da177e4SLinus Torvalds unsigned int level; 1191da177e4SLinus Torvalds 1201da177e4SLinus Torvalds /* 1211da177e4SLinus Torvalds * If ML QUEUE log level is greater than or equal to: 1221da177e4SLinus Torvalds * 1231da177e4SLinus Torvalds * 1: nothing (match completion) 1241da177e4SLinus Torvalds * 125c11c004bSHannes Reinecke * 2: log opcode + command of all commands + cmd address 1261da177e4SLinus Torvalds * 127c11c004bSHannes Reinecke * 3: same as 2 1281da177e4SLinus Torvalds * 129a4a6afb4SHannes Reinecke * 4: same as 3 1301da177e4SLinus Torvalds */ 1311da177e4SLinus Torvalds if (unlikely(scsi_logging_level)) { 1321da177e4SLinus Torvalds level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT, 1331da177e4SLinus Torvalds SCSI_LOG_MLQUEUE_BITS); 1341da177e4SLinus Torvalds if (level > 1) { 135c11c004bSHannes Reinecke scmd_printk(KERN_INFO, cmd, 136c11c004bSHannes Reinecke "Send: scmd 0x%p\n", cmd); 1371da177e4SLinus Torvalds scsi_print_command(cmd); 1381da177e4SLinus Torvalds } 1391da177e4SLinus Torvalds } 1401da177e4SLinus Torvalds } 1411da177e4SLinus Torvalds 1421da177e4SLinus Torvalds void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) 1431da177e4SLinus Torvalds { 1441da177e4SLinus Torvalds unsigned int level; 1451da177e4SLinus Torvalds 1461da177e4SLinus Torvalds /* 1471da177e4SLinus Torvalds * If ML COMPLETE log level is greater than or equal to: 1481da177e4SLinus Torvalds * 1491da177e4SLinus Torvalds * 1: log disposition, result, opcode + command, and conditionally 1501da177e4SLinus Torvalds * sense data for failures or non SUCCESS dispositions. 1511da177e4SLinus Torvalds * 1521da177e4SLinus Torvalds * 2: same as 1 but for all command completions. 1531da177e4SLinus Torvalds * 154c11c004bSHannes Reinecke * 3: same as 2 1551da177e4SLinus Torvalds * 1561da177e4SLinus Torvalds * 4: same as 3 plus dump extra junk 1571da177e4SLinus Torvalds */ 1581da177e4SLinus Torvalds if (unlikely(scsi_logging_level)) { 1591da177e4SLinus Torvalds level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT, 1601da177e4SLinus Torvalds SCSI_LOG_MLCOMPLETE_BITS); 1611da177e4SLinus Torvalds if (((level > 0) && (cmd->result || disposition != SUCCESS)) || 1621da177e4SLinus Torvalds (level > 1)) { 163026f8da8SHannes Reinecke scsi_print_result(cmd, "Done", disposition); 1641da177e4SLinus Torvalds scsi_print_command(cmd); 165a4d04a4cSMartin K. Petersen if (status_byte(cmd->result) & CHECK_CONDITION) 166d811b848SHannes Reinecke scsi_print_sense(cmd); 167a4d04a4cSMartin K. Petersen if (level > 3) 168a4d04a4cSMartin K. Petersen scmd_printk(KERN_INFO, cmd, 169a4d04a4cSMartin K. Petersen "scsi host busy %d failed %d\n", 17074665016SChristoph Hellwig atomic_read(&cmd->device->host->host_busy), 171a4d04a4cSMartin K. Petersen cmd->device->host->host_failed); 1721da177e4SLinus Torvalds } 1731da177e4SLinus Torvalds } 1741da177e4SLinus Torvalds } 1751da177e4SLinus Torvalds #endif 1761da177e4SLinus Torvalds 177eb44820cSRob Landley /** 178eb44820cSRob Landley * scsi_cmd_get_serial - Assign a serial number to a command 179eb44820cSRob Landley * @host: the scsi host 180eb44820cSRob Landley * @cmd: command to assign serial number to 181eb44820cSRob Landley * 182eb44820cSRob Landley * Description: a serial number identifies a request for error recovery 1831da177e4SLinus Torvalds * and debugging purposes. Protected by the Host_Lock of host. 1841da177e4SLinus Torvalds */ 185f281233dSJeff Garzik void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd *cmd) 1861da177e4SLinus Torvalds { 1871da177e4SLinus Torvalds cmd->serial_number = host->cmd_serial_number++; 1881da177e4SLinus Torvalds if (cmd->serial_number == 0) 1891da177e4SLinus Torvalds cmd->serial_number = host->cmd_serial_number++; 1901da177e4SLinus Torvalds } 191f281233dSJeff Garzik EXPORT_SYMBOL(scsi_cmd_get_serial); 1921da177e4SLinus Torvalds 193eb44820cSRob Landley /** 194eb44820cSRob Landley * scsi_finish_command - cleanup and pass command back to upper layer 195eb44820cSRob Landley * @cmd: the command 1961da177e4SLinus Torvalds * 197eb44820cSRob Landley * Description: Pass command off to upper layer for finishing of I/O 1981da177e4SLinus Torvalds * request, waking processes that are waiting on results, 1991da177e4SLinus Torvalds * etc. 2001da177e4SLinus Torvalds */ 2011da177e4SLinus Torvalds void scsi_finish_command(struct scsi_cmnd *cmd) 2021da177e4SLinus Torvalds { 2031da177e4SLinus Torvalds struct scsi_device *sdev = cmd->device; 204f0c0a376SMike Christie struct scsi_target *starget = scsi_target(sdev); 2051da177e4SLinus Torvalds struct Scsi_Host *shost = sdev->host; 2067b3d9545SLinus Torvalds struct scsi_driver *drv; 2077b3d9545SLinus Torvalds unsigned int good_bytes; 2081da177e4SLinus Torvalds 2091da177e4SLinus Torvalds scsi_device_unbusy(sdev); 2101da177e4SLinus Torvalds 2111da177e4SLinus Torvalds /* 212cd9070c9SChristoph Hellwig * Clear the flags that say that the device/target/host is no longer 213cd9070c9SChristoph Hellwig * capable of accepting new commands. 2141da177e4SLinus Torvalds */ 215cd9070c9SChristoph Hellwig if (atomic_read(&shost->host_blocked)) 216cd9070c9SChristoph Hellwig atomic_set(&shost->host_blocked, 0); 217cd9070c9SChristoph Hellwig if (atomic_read(&starget->target_blocked)) 218cd9070c9SChristoph Hellwig atomic_set(&starget->target_blocked, 0); 219cd9070c9SChristoph Hellwig if (atomic_read(&sdev->device_blocked)) 220cd9070c9SChristoph Hellwig atomic_set(&sdev->device_blocked, 0); 2211da177e4SLinus Torvalds 2221da177e4SLinus Torvalds /* 2231da177e4SLinus Torvalds * If we have valid sense information, then some kind of recovery 2241da177e4SLinus Torvalds * must have taken place. Make a note of this. 2251da177e4SLinus Torvalds */ 2261da177e4SLinus Torvalds if (SCSI_SENSE_VALID(cmd)) 2271da177e4SLinus Torvalds cmd->result |= (DRIVER_SENSE << 24); 2281da177e4SLinus Torvalds 2293bf743e7SJeff Garzik SCSI_LOG_MLCOMPLETE(4, sdev_printk(KERN_INFO, sdev, 2303bf743e7SJeff Garzik "Notifying upper driver of completion " 2313bf743e7SJeff Garzik "(result %x)\n", cmd->result)); 2321da177e4SLinus Torvalds 233f18573abSFUJITA Tomonori good_bytes = scsi_bufflen(cmd); 23457292b58SChristoph Hellwig if (!blk_rq_is_passthrough(cmd->request)) { 235427e59f0SJames Bottomley int old_good_bytes = good_bytes; 2367b3d9545SLinus Torvalds drv = scsi_cmd_to_driver(cmd); 2377b3d9545SLinus Torvalds if (drv->done) 2387b3d9545SLinus Torvalds good_bytes = drv->done(cmd); 239427e59f0SJames Bottomley /* 240427e59f0SJames Bottomley * USB may not give sense identifying bad sector and 241427e59f0SJames Bottomley * simply return a residue instead, so subtract off the 242427e59f0SJames Bottomley * residue if drv->done() error processing indicates no 243427e59f0SJames Bottomley * change to the completion length. 244427e59f0SJames Bottomley */ 245427e59f0SJames Bottomley if (good_bytes == old_good_bytes) 246427e59f0SJames Bottomley good_bytes -= scsi_get_resid(cmd); 2477b3d9545SLinus Torvalds } 2487b3d9545SLinus Torvalds scsi_io_completion(cmd, good_bytes); 2491da177e4SLinus Torvalds } 2501da177e4SLinus Torvalds 251eb44820cSRob Landley /** 252db5ed4dfSChristoph Hellwig * scsi_change_queue_depth - change a device's queue depth 253eb44820cSRob Landley * @sdev: SCSI Device in question 254db5ed4dfSChristoph Hellwig * @depth: number of commands allowed to be queued to the driver 2551da177e4SLinus Torvalds * 256db5ed4dfSChristoph Hellwig * Sets the device queue depth and returns the new value. 2571da177e4SLinus Torvalds */ 258db5ed4dfSChristoph Hellwig int scsi_change_queue_depth(struct scsi_device *sdev, int depth) 2591da177e4SLinus Torvalds { 26064d513acSChristoph Hellwig if (depth > 0) { 26164d513acSChristoph Hellwig sdev->queue_depth = depth; 26264d513acSChristoph Hellwig wmb(); 263885ace9eSMike Christie } 2641da177e4SLinus Torvalds 265d278d4a8SJens Axboe if (sdev->request_queue) 266d278d4a8SJens Axboe blk_set_queue_depth(sdev->request_queue, depth); 267d278d4a8SJens Axboe 268db5ed4dfSChristoph Hellwig return sdev->queue_depth; 2691da177e4SLinus Torvalds } 270db5ed4dfSChristoph Hellwig EXPORT_SYMBOL(scsi_change_queue_depth); 2711da177e4SLinus Torvalds 272eb44820cSRob Landley /** 273eb44820cSRob Landley * scsi_track_queue_full - track QUEUE_FULL events to adjust queue depth 274eb44820cSRob Landley * @sdev: SCSI Device in question 275eb44820cSRob Landley * @depth: Current number of outstanding SCSI commands on this device, 276eb44820cSRob Landley * not counting the one returned as QUEUE_FULL. 2771da177e4SLinus Torvalds * 278eb44820cSRob Landley * Description: This function will track successive QUEUE_FULL events on a 2791da177e4SLinus Torvalds * specific SCSI device to determine if and when there is a 2801da177e4SLinus Torvalds * need to adjust the queue depth on the device. 2811da177e4SLinus Torvalds * 282eb44820cSRob Landley * Returns: 0 - No change needed, >0 - Adjust queue depth to this new depth, 2831da177e4SLinus Torvalds * -1 - Drop back to untagged operation using host->cmd_per_lun 2841da177e4SLinus Torvalds * as the untagged command depth 2851da177e4SLinus Torvalds * 2861da177e4SLinus Torvalds * Lock Status: None held on entry 2871da177e4SLinus Torvalds * 2881da177e4SLinus Torvalds * Notes: Low level drivers may call this at any time and we will do 2891da177e4SLinus Torvalds * "The Right Thing." We are interrupt context safe. 2901da177e4SLinus Torvalds */ 2911da177e4SLinus Torvalds int scsi_track_queue_full(struct scsi_device *sdev, int depth) 2921da177e4SLinus Torvalds { 2934a84067dSVasu Dev 2944a84067dSVasu Dev /* 2954a84067dSVasu Dev * Don't let QUEUE_FULLs on the same 2964a84067dSVasu Dev * jiffies count, they could all be from 2974a84067dSVasu Dev * same event. 2984a84067dSVasu Dev */ 2994a84067dSVasu Dev if ((jiffies >> 4) == (sdev->last_queue_full_time >> 4)) 3001da177e4SLinus Torvalds return 0; 3011da177e4SLinus Torvalds 3024a84067dSVasu Dev sdev->last_queue_full_time = jiffies; 3031da177e4SLinus Torvalds if (sdev->last_queue_full_depth != depth) { 3041da177e4SLinus Torvalds sdev->last_queue_full_count = 1; 3051da177e4SLinus Torvalds sdev->last_queue_full_depth = depth; 3061da177e4SLinus Torvalds } else { 3071da177e4SLinus Torvalds sdev->last_queue_full_count++; 3081da177e4SLinus Torvalds } 3091da177e4SLinus Torvalds 3101da177e4SLinus Torvalds if (sdev->last_queue_full_count <= 10) 3111da177e4SLinus Torvalds return 0; 3121da177e4SLinus Torvalds 313db5ed4dfSChristoph Hellwig return scsi_change_queue_depth(sdev, depth); 3141da177e4SLinus Torvalds } 3151da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_track_queue_full); 3161da177e4SLinus Torvalds 3171da177e4SLinus Torvalds /** 318881a256dSMatthew Wilcox * scsi_vpd_inquiry - Request a device provide us with a VPD page 319881a256dSMatthew Wilcox * @sdev: The device to ask 320881a256dSMatthew Wilcox * @buffer: Where to put the result 321881a256dSMatthew Wilcox * @page: Which Vital Product Data to return 322881a256dSMatthew Wilcox * @len: The length of the buffer 323881a256dSMatthew Wilcox * 324881a256dSMatthew Wilcox * This is an internal helper function. You probably want to use 325881a256dSMatthew Wilcox * scsi_get_vpd_page instead. 326881a256dSMatthew Wilcox * 327bc8945dfSHannes Reinecke * Returns size of the vpd page on success or a negative error number. 328881a256dSMatthew Wilcox */ 329881a256dSMatthew Wilcox static int scsi_vpd_inquiry(struct scsi_device *sdev, unsigned char *buffer, 330881a256dSMatthew Wilcox u8 page, unsigned len) 331881a256dSMatthew Wilcox { 332881a256dSMatthew Wilcox int result; 333881a256dSMatthew Wilcox unsigned char cmd[16]; 334881a256dSMatthew Wilcox 335bc8945dfSHannes Reinecke if (len < 4) 336bc8945dfSHannes Reinecke return -EINVAL; 337bc8945dfSHannes Reinecke 338881a256dSMatthew Wilcox cmd[0] = INQUIRY; 339881a256dSMatthew Wilcox cmd[1] = 1; /* EVPD */ 340881a256dSMatthew Wilcox cmd[2] = page; 341881a256dSMatthew Wilcox cmd[3] = len >> 8; 342881a256dSMatthew Wilcox cmd[4] = len & 0xff; 343881a256dSMatthew Wilcox cmd[5] = 0; /* Control byte */ 344881a256dSMatthew Wilcox 345881a256dSMatthew Wilcox /* 346881a256dSMatthew Wilcox * I'm not convinced we need to try quite this hard to get VPD, but 347881a256dSMatthew Wilcox * all the existing users tried this hard. 348881a256dSMatthew Wilcox */ 349881a256dSMatthew Wilcox result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, 35095a3639eSJames Bottomley len, NULL, 30 * HZ, 3, NULL); 351881a256dSMatthew Wilcox if (result) 352bc8945dfSHannes Reinecke return -EIO; 353881a256dSMatthew Wilcox 354881a256dSMatthew Wilcox /* Sanity check that we got the page back that we asked for */ 355881a256dSMatthew Wilcox if (buffer[1] != page) 356881a256dSMatthew Wilcox return -EIO; 357881a256dSMatthew Wilcox 358bc8945dfSHannes Reinecke return get_unaligned_be16(&buffer[2]) + 4; 359881a256dSMatthew Wilcox } 360881a256dSMatthew Wilcox 361881a256dSMatthew Wilcox /** 362881a256dSMatthew Wilcox * scsi_get_vpd_page - Get Vital Product Data from a SCSI device 363881a256dSMatthew Wilcox * @sdev: The device to ask 364881a256dSMatthew Wilcox * @page: Which Vital Product Data to return 365786f8ba2SRandy Dunlap * @buf: where to store the VPD 366786f8ba2SRandy Dunlap * @buf_len: number of bytes in the VPD buffer area 367881a256dSMatthew Wilcox * 368881a256dSMatthew Wilcox * SCSI devices may optionally supply Vital Product Data. Each 'page' 369881a256dSMatthew Wilcox * of VPD is defined in the appropriate SCSI document (eg SPC, SBC). 370881a256dSMatthew Wilcox * If the device supports this VPD page, this routine returns a pointer 371881a256dSMatthew Wilcox * to a buffer containing the data from that page. The caller is 372881a256dSMatthew Wilcox * responsible for calling kfree() on this pointer when it is no longer 373881a256dSMatthew Wilcox * needed. If we cannot retrieve the VPD page this routine returns %NULL. 374881a256dSMatthew Wilcox */ 375e3deec09SJames Bottomley int scsi_get_vpd_page(struct scsi_device *sdev, u8 page, unsigned char *buf, 376e3deec09SJames Bottomley int buf_len) 377881a256dSMatthew Wilcox { 378881a256dSMatthew Wilcox int i, result; 379881a256dSMatthew Wilcox 3807562523eSMartin K. Petersen if (sdev->skip_vpd_pages) 3817562523eSMartin K. Petersen goto fail; 3827562523eSMartin K. Petersen 383881a256dSMatthew Wilcox /* Ask for all the pages supported by this device */ 384e3deec09SJames Bottomley result = scsi_vpd_inquiry(sdev, buf, 0, buf_len); 385bc8945dfSHannes Reinecke if (result < 4) 386881a256dSMatthew Wilcox goto fail; 387881a256dSMatthew Wilcox 388881a256dSMatthew Wilcox /* If the user actually wanted this page, we can skip the rest */ 389881a256dSMatthew Wilcox if (page == 0) 39016d3ea26SMartin K. Petersen return 0; 391881a256dSMatthew Wilcox 392bc8945dfSHannes Reinecke for (i = 4; i < min(result, buf_len); i++) 393bc8945dfSHannes Reinecke if (buf[i] == page) 394881a256dSMatthew Wilcox goto found; 395e3deec09SJames Bottomley 396bc8945dfSHannes Reinecke if (i < result && i >= buf_len) 397e3deec09SJames Bottomley /* ran off the end of the buffer, give us benefit of doubt */ 398e3deec09SJames Bottomley goto found; 399881a256dSMatthew Wilcox /* The device claims it doesn't support the requested page */ 400881a256dSMatthew Wilcox goto fail; 401881a256dSMatthew Wilcox 402881a256dSMatthew Wilcox found: 403e3deec09SJames Bottomley result = scsi_vpd_inquiry(sdev, buf, page, buf_len); 404bc8945dfSHannes Reinecke if (result < 0) 405881a256dSMatthew Wilcox goto fail; 406881a256dSMatthew Wilcox 407e3deec09SJames Bottomley return 0; 408881a256dSMatthew Wilcox 409881a256dSMatthew Wilcox fail: 410e3deec09SJames Bottomley return -EINVAL; 411881a256dSMatthew Wilcox } 412881a256dSMatthew Wilcox EXPORT_SYMBOL_GPL(scsi_get_vpd_page); 413881a256dSMatthew Wilcox 414881a256dSMatthew Wilcox /** 415b3ae8780SHannes Reinecke * scsi_attach_vpd - Attach Vital Product Data to a SCSI device structure 416b3ae8780SHannes Reinecke * @sdev: The device to ask 417b3ae8780SHannes Reinecke * 418b3ae8780SHannes Reinecke * Attach the 'Device Identification' VPD page (0x83) and the 419b3ae8780SHannes Reinecke * 'Unit Serial Number' VPD page (0x80) to a SCSI device 420b3ae8780SHannes Reinecke * structure. This information can be used to identify the device 421b3ae8780SHannes Reinecke * uniquely. 422b3ae8780SHannes Reinecke */ 423b3ae8780SHannes Reinecke void scsi_attach_vpd(struct scsi_device *sdev) 424b3ae8780SHannes Reinecke { 425b3ae8780SHannes Reinecke int result, i; 426b3ae8780SHannes Reinecke int vpd_len = SCSI_VPD_PG_LEN; 427b3ae8780SHannes Reinecke int pg80_supported = 0; 428b3ae8780SHannes Reinecke int pg83_supported = 0; 42909e2b0b1SHannes Reinecke unsigned char __rcu *vpd_buf, *orig_vpd_buf = NULL; 430b3ae8780SHannes Reinecke 4315ddfe085SHannes Reinecke if (!scsi_device_supports_vpd(sdev)) 432b3ae8780SHannes Reinecke return; 4335ddfe085SHannes Reinecke 434b3ae8780SHannes Reinecke retry_pg0: 435b3ae8780SHannes Reinecke vpd_buf = kmalloc(vpd_len, GFP_KERNEL); 436b3ae8780SHannes Reinecke if (!vpd_buf) 437b3ae8780SHannes Reinecke return; 438b3ae8780SHannes Reinecke 439b3ae8780SHannes Reinecke /* Ask for all the pages supported by this device */ 440b3ae8780SHannes Reinecke result = scsi_vpd_inquiry(sdev, vpd_buf, 0, vpd_len); 441b3ae8780SHannes Reinecke if (result < 0) { 442b3ae8780SHannes Reinecke kfree(vpd_buf); 443b3ae8780SHannes Reinecke return; 444b3ae8780SHannes Reinecke } 445b3ae8780SHannes Reinecke if (result > vpd_len) { 446b3ae8780SHannes Reinecke vpd_len = result; 447b3ae8780SHannes Reinecke kfree(vpd_buf); 448b3ae8780SHannes Reinecke goto retry_pg0; 449b3ae8780SHannes Reinecke } 450b3ae8780SHannes Reinecke 451b3ae8780SHannes Reinecke for (i = 4; i < result; i++) { 452b3ae8780SHannes Reinecke if (vpd_buf[i] == 0x80) 453b3ae8780SHannes Reinecke pg80_supported = 1; 454b3ae8780SHannes Reinecke if (vpd_buf[i] == 0x83) 455b3ae8780SHannes Reinecke pg83_supported = 1; 456b3ae8780SHannes Reinecke } 457b3ae8780SHannes Reinecke kfree(vpd_buf); 458b3ae8780SHannes Reinecke vpd_len = SCSI_VPD_PG_LEN; 459b3ae8780SHannes Reinecke 460b3ae8780SHannes Reinecke if (pg80_supported) { 461b3ae8780SHannes Reinecke retry_pg80: 462b3ae8780SHannes Reinecke vpd_buf = kmalloc(vpd_len, GFP_KERNEL); 463b3ae8780SHannes Reinecke if (!vpd_buf) 464b3ae8780SHannes Reinecke return; 465b3ae8780SHannes Reinecke 466b3ae8780SHannes Reinecke result = scsi_vpd_inquiry(sdev, vpd_buf, 0x80, vpd_len); 467b3ae8780SHannes Reinecke if (result < 0) { 468b3ae8780SHannes Reinecke kfree(vpd_buf); 469b3ae8780SHannes Reinecke return; 470b3ae8780SHannes Reinecke } 471b3ae8780SHannes Reinecke if (result > vpd_len) { 472b3ae8780SHannes Reinecke vpd_len = result; 473b3ae8780SHannes Reinecke kfree(vpd_buf); 474b3ae8780SHannes Reinecke goto retry_pg80; 475b3ae8780SHannes Reinecke } 47609e2b0b1SHannes Reinecke mutex_lock(&sdev->inquiry_mutex); 47709e2b0b1SHannes Reinecke orig_vpd_buf = sdev->vpd_pg80; 478b3ae8780SHannes Reinecke sdev->vpd_pg80_len = result; 47909e2b0b1SHannes Reinecke rcu_assign_pointer(sdev->vpd_pg80, vpd_buf); 48009e2b0b1SHannes Reinecke mutex_unlock(&sdev->inquiry_mutex); 48109e2b0b1SHannes Reinecke synchronize_rcu(); 48209e2b0b1SHannes Reinecke if (orig_vpd_buf) { 48309e2b0b1SHannes Reinecke kfree(orig_vpd_buf); 48409e2b0b1SHannes Reinecke orig_vpd_buf = NULL; 48509e2b0b1SHannes Reinecke } 486b3ae8780SHannes Reinecke vpd_len = SCSI_VPD_PG_LEN; 487b3ae8780SHannes Reinecke } 488b3ae8780SHannes Reinecke 489b3ae8780SHannes Reinecke if (pg83_supported) { 490b3ae8780SHannes Reinecke retry_pg83: 491b3ae8780SHannes Reinecke vpd_buf = kmalloc(vpd_len, GFP_KERNEL); 492b3ae8780SHannes Reinecke if (!vpd_buf) 493b3ae8780SHannes Reinecke return; 494b3ae8780SHannes Reinecke 495b3ae8780SHannes Reinecke result = scsi_vpd_inquiry(sdev, vpd_buf, 0x83, vpd_len); 496b3ae8780SHannes Reinecke if (result < 0) { 497b3ae8780SHannes Reinecke kfree(vpd_buf); 498b3ae8780SHannes Reinecke return; 499b3ae8780SHannes Reinecke } 500b3ae8780SHannes Reinecke if (result > vpd_len) { 501b3ae8780SHannes Reinecke vpd_len = result; 502b3ae8780SHannes Reinecke kfree(vpd_buf); 503b3ae8780SHannes Reinecke goto retry_pg83; 504b3ae8780SHannes Reinecke } 50509e2b0b1SHannes Reinecke mutex_lock(&sdev->inquiry_mutex); 50609e2b0b1SHannes Reinecke orig_vpd_buf = sdev->vpd_pg83; 507b3ae8780SHannes Reinecke sdev->vpd_pg83_len = result; 50809e2b0b1SHannes Reinecke rcu_assign_pointer(sdev->vpd_pg83, vpd_buf); 50909e2b0b1SHannes Reinecke mutex_unlock(&sdev->inquiry_mutex); 51009e2b0b1SHannes Reinecke synchronize_rcu(); 51109e2b0b1SHannes Reinecke if (orig_vpd_buf) 51209e2b0b1SHannes Reinecke kfree(orig_vpd_buf); 513b3ae8780SHannes Reinecke } 514b3ae8780SHannes Reinecke } 515b3ae8780SHannes Reinecke 516b3ae8780SHannes Reinecke /** 5173c6bdaeaSMartin K. Petersen * scsi_report_opcode - Find out if a given command opcode is supported 5183c6bdaeaSMartin K. Petersen * @sdev: scsi device to query 5193c6bdaeaSMartin K. Petersen * @buffer: scratch buffer (must be at least 20 bytes long) 5203c6bdaeaSMartin K. Petersen * @len: length of buffer 5213c6bdaeaSMartin K. Petersen * @opcode: opcode for command to look up 5223c6bdaeaSMartin K. Petersen * 5233c6bdaeaSMartin K. Petersen * Uses the REPORT SUPPORTED OPERATION CODES to look up the given 52466c28f97SMartin K. Petersen * opcode. Returns -EINVAL if RSOC fails, 0 if the command opcode is 52566c28f97SMartin K. Petersen * unsupported and 1 if the device claims to support the command. 5263c6bdaeaSMartin K. Petersen */ 5273c6bdaeaSMartin K. Petersen int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer, 5283c6bdaeaSMartin K. Petersen unsigned int len, unsigned char opcode) 5293c6bdaeaSMartin K. Petersen { 5303c6bdaeaSMartin K. Petersen unsigned char cmd[16]; 5313c6bdaeaSMartin K. Petersen struct scsi_sense_hdr sshdr; 5323c6bdaeaSMartin K. Petersen int result; 5333c6bdaeaSMartin K. Petersen 5343c6bdaeaSMartin K. Petersen if (sdev->no_report_opcodes || sdev->scsi_level < SCSI_SPC_3) 53566c28f97SMartin K. Petersen return -EINVAL; 5363c6bdaeaSMartin K. Petersen 5373c6bdaeaSMartin K. Petersen memset(cmd, 0, 16); 5383c6bdaeaSMartin K. Petersen cmd[0] = MAINTENANCE_IN; 5393c6bdaeaSMartin K. Petersen cmd[1] = MI_REPORT_SUPPORTED_OPERATION_CODES; 5403c6bdaeaSMartin K. Petersen cmd[2] = 1; /* One command format */ 5413c6bdaeaSMartin K. Petersen cmd[3] = opcode; 5423c6bdaeaSMartin K. Petersen put_unaligned_be32(len, &cmd[6]); 5433c6bdaeaSMartin K. Petersen memset(buffer, 0, len); 5443c6bdaeaSMartin K. Petersen 5453c6bdaeaSMartin K. Petersen result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len, 5463c6bdaeaSMartin K. Petersen &sshdr, 30 * HZ, 3, NULL); 5473c6bdaeaSMartin K. Petersen 5483c6bdaeaSMartin K. Petersen if (result && scsi_sense_valid(&sshdr) && 5493c6bdaeaSMartin K. Petersen sshdr.sense_key == ILLEGAL_REQUEST && 5503c6bdaeaSMartin K. Petersen (sshdr.asc == 0x20 || sshdr.asc == 0x24) && sshdr.ascq == 0x00) 55166c28f97SMartin K. Petersen return -EINVAL; 5523c6bdaeaSMartin K. Petersen 5533c6bdaeaSMartin K. Petersen if ((buffer[1] & 3) == 3) /* Command supported */ 5543c6bdaeaSMartin K. Petersen return 1; 5553c6bdaeaSMartin K. Petersen 5563c6bdaeaSMartin K. Petersen return 0; 5573c6bdaeaSMartin K. Petersen } 5583c6bdaeaSMartin K. Petersen EXPORT_SYMBOL(scsi_report_opcode); 5593c6bdaeaSMartin K. Petersen 5603c6bdaeaSMartin K. Petersen /** 561eb44820cSRob Landley * scsi_device_get - get an additional reference to a scsi_device 5621da177e4SLinus Torvalds * @sdev: device to get a reference to 5631da177e4SLinus Torvalds * 564eb44820cSRob Landley * Description: Gets a reference to the scsi_device and increments the use count 5651da177e4SLinus Torvalds * of the underlying LLDD module. You must hold host_lock of the 5661da177e4SLinus Torvalds * parent Scsi_Host or already have a reference when calling this. 567cff549e4SChristoph Hellwig * 568cff549e4SChristoph Hellwig * This will fail if a device is deleted or cancelled, or when the LLD module 569cff549e4SChristoph Hellwig * is in the process of being unloaded. 5701da177e4SLinus Torvalds */ 5711da177e4SLinus Torvalds int scsi_device_get(struct scsi_device *sdev) 5721da177e4SLinus Torvalds { 573cff549e4SChristoph Hellwig if (sdev->sdev_state == SDEV_DEL || sdev->sdev_state == SDEV_CANCEL) 574cff549e4SChristoph Hellwig goto fail; 5751da177e4SLinus Torvalds if (!get_device(&sdev->sdev_gendev)) 576cff549e4SChristoph Hellwig goto fail; 577cff549e4SChristoph Hellwig if (!try_module_get(sdev->host->hostt->module)) 578cff549e4SChristoph Hellwig goto fail_put_device; 5791da177e4SLinus Torvalds return 0; 580cff549e4SChristoph Hellwig 581cff549e4SChristoph Hellwig fail_put_device: 582cff549e4SChristoph Hellwig put_device(&sdev->sdev_gendev); 583cff549e4SChristoph Hellwig fail: 584cff549e4SChristoph Hellwig return -ENXIO; 5851da177e4SLinus Torvalds } 5861da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_get); 5871da177e4SLinus Torvalds 5881da177e4SLinus Torvalds /** 5891da177e4SLinus Torvalds * scsi_device_put - release a reference to a scsi_device 5901da177e4SLinus Torvalds * @sdev: device to release a reference on. 5911da177e4SLinus Torvalds * 592eb44820cSRob Landley * Description: Release a reference to the scsi_device and decrements the use 593eb44820cSRob Landley * count of the underlying LLDD module. The device is freed once the last 5941da177e4SLinus Torvalds * user vanishes. 5951da177e4SLinus Torvalds */ 5961da177e4SLinus Torvalds void scsi_device_put(struct scsi_device *sdev) 5971da177e4SLinus Torvalds { 598dc4515eaSRusty Russell module_put(sdev->host->hostt->module); 5991da177e4SLinus Torvalds put_device(&sdev->sdev_gendev); 6001da177e4SLinus Torvalds } 6011da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_put); 6021da177e4SLinus Torvalds 603eb44820cSRob Landley /* helper for shost_for_each_device, see that for documentation */ 6041da177e4SLinus Torvalds struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost, 6051da177e4SLinus Torvalds struct scsi_device *prev) 6061da177e4SLinus Torvalds { 6071da177e4SLinus Torvalds struct list_head *list = (prev ? &prev->siblings : &shost->__devices); 6081da177e4SLinus Torvalds struct scsi_device *next = NULL; 6091da177e4SLinus Torvalds unsigned long flags; 6101da177e4SLinus Torvalds 6111da177e4SLinus Torvalds spin_lock_irqsave(shost->host_lock, flags); 6121da177e4SLinus Torvalds while (list->next != &shost->__devices) { 6131da177e4SLinus Torvalds next = list_entry(list->next, struct scsi_device, siblings); 6141da177e4SLinus Torvalds /* skip devices that we can't get a reference to */ 6151da177e4SLinus Torvalds if (!scsi_device_get(next)) 6161da177e4SLinus Torvalds break; 6171da177e4SLinus Torvalds next = NULL; 6181da177e4SLinus Torvalds list = list->next; 6191da177e4SLinus Torvalds } 6201da177e4SLinus Torvalds spin_unlock_irqrestore(shost->host_lock, flags); 6211da177e4SLinus Torvalds 6221da177e4SLinus Torvalds if (prev) 6231da177e4SLinus Torvalds scsi_device_put(prev); 6241da177e4SLinus Torvalds return next; 6251da177e4SLinus Torvalds } 6261da177e4SLinus Torvalds EXPORT_SYMBOL(__scsi_iterate_devices); 6271da177e4SLinus Torvalds 6281da177e4SLinus Torvalds /** 6291da177e4SLinus Torvalds * starget_for_each_device - helper to walk all devices of a target 6301da177e4SLinus Torvalds * @starget: target whose devices we want to iterate over. 631eb44820cSRob Landley * @data: Opaque passed to each function call. 632eb44820cSRob Landley * @fn: Function to call on each device 6331da177e4SLinus Torvalds * 634522939d4SMaciej W. Rozycki * This traverses over each device of @starget. The devices have 6351da177e4SLinus Torvalds * a reference that must be released by scsi_host_put when breaking 6361da177e4SLinus Torvalds * out of the loop. 6371da177e4SLinus Torvalds */ 6381da177e4SLinus Torvalds void starget_for_each_device(struct scsi_target *starget, void *data, 6391da177e4SLinus Torvalds void (*fn)(struct scsi_device *, void *)) 6401da177e4SLinus Torvalds { 6411da177e4SLinus Torvalds struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 6421da177e4SLinus Torvalds struct scsi_device *sdev; 6431da177e4SLinus Torvalds 6441da177e4SLinus Torvalds shost_for_each_device(sdev, shost) { 6451da177e4SLinus Torvalds if ((sdev->channel == starget->channel) && 6461da177e4SLinus Torvalds (sdev->id == starget->id)) 6471da177e4SLinus Torvalds fn(sdev, data); 6481da177e4SLinus Torvalds } 6491da177e4SLinus Torvalds } 6501da177e4SLinus Torvalds EXPORT_SYMBOL(starget_for_each_device); 6511da177e4SLinus Torvalds 6521da177e4SLinus Torvalds /** 65314f501a4SRandy Dunlap * __starget_for_each_device - helper to walk all devices of a target (UNLOCKED) 654522939d4SMaciej W. Rozycki * @starget: target whose devices we want to iterate over. 65514f501a4SRandy Dunlap * @data: parameter for callback @fn() 65614f501a4SRandy Dunlap * @fn: callback function that is invoked for each device 657522939d4SMaciej W. Rozycki * 658522939d4SMaciej W. Rozycki * This traverses over each device of @starget. It does _not_ 659522939d4SMaciej W. Rozycki * take a reference on the scsi_device, so the whole loop must be 660522939d4SMaciej W. Rozycki * protected by shost->host_lock. 661522939d4SMaciej W. Rozycki * 662522939d4SMaciej W. Rozycki * Note: The only reason why drivers would want to use this is because 663522939d4SMaciej W. Rozycki * they need to access the device list in irq context. Otherwise you 664522939d4SMaciej W. Rozycki * really want to use starget_for_each_device instead. 665522939d4SMaciej W. Rozycki **/ 666522939d4SMaciej W. Rozycki void __starget_for_each_device(struct scsi_target *starget, void *data, 667522939d4SMaciej W. Rozycki void (*fn)(struct scsi_device *, void *)) 668522939d4SMaciej W. Rozycki { 669522939d4SMaciej W. Rozycki struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 670522939d4SMaciej W. Rozycki struct scsi_device *sdev; 671522939d4SMaciej W. Rozycki 672522939d4SMaciej W. Rozycki __shost_for_each_device(sdev, shost) { 673522939d4SMaciej W. Rozycki if ((sdev->channel == starget->channel) && 674522939d4SMaciej W. Rozycki (sdev->id == starget->id)) 675522939d4SMaciej W. Rozycki fn(sdev, data); 676522939d4SMaciej W. Rozycki } 677522939d4SMaciej W. Rozycki } 678522939d4SMaciej W. Rozycki EXPORT_SYMBOL(__starget_for_each_device); 679522939d4SMaciej W. Rozycki 680522939d4SMaciej W. Rozycki /** 6811da177e4SLinus Torvalds * __scsi_device_lookup_by_target - find a device given the target (UNLOCKED) 6821da177e4SLinus Torvalds * @starget: SCSI target pointer 6831da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 6841da177e4SLinus Torvalds * 685eb44820cSRob Landley * Description: Looks up the scsi_device with the specified @lun for a given 6861da177e4SLinus Torvalds * @starget. The returned scsi_device does not have an additional 6871da177e4SLinus Torvalds * reference. You must hold the host's host_lock over this call and 68832aeef60SHannes Reinecke * any access to the returned scsi_device. A scsi_device in state 68932aeef60SHannes Reinecke * SDEV_DEL is skipped. 6901da177e4SLinus Torvalds * 691dc8875e1SRandy Dunlap * Note: The only reason why drivers should use this is because 692eb44820cSRob Landley * they need to access the device list in irq context. Otherwise you 6931da177e4SLinus Torvalds * really want to use scsi_device_lookup_by_target instead. 6941da177e4SLinus Torvalds **/ 6951da177e4SLinus Torvalds struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget, 6969cb78c16SHannes Reinecke u64 lun) 6971da177e4SLinus Torvalds { 6981da177e4SLinus Torvalds struct scsi_device *sdev; 6991da177e4SLinus Torvalds 7001da177e4SLinus Torvalds list_for_each_entry(sdev, &starget->devices, same_target_siblings) { 70132aeef60SHannes Reinecke if (sdev->sdev_state == SDEV_DEL) 70232aeef60SHannes Reinecke continue; 7031da177e4SLinus Torvalds if (sdev->lun ==lun) 7041da177e4SLinus Torvalds return sdev; 7051da177e4SLinus Torvalds } 7061da177e4SLinus Torvalds 7071da177e4SLinus Torvalds return NULL; 7081da177e4SLinus Torvalds } 7091da177e4SLinus Torvalds EXPORT_SYMBOL(__scsi_device_lookup_by_target); 7101da177e4SLinus Torvalds 7111da177e4SLinus Torvalds /** 7121da177e4SLinus Torvalds * scsi_device_lookup_by_target - find a device given the target 7131da177e4SLinus Torvalds * @starget: SCSI target pointer 7141da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 7151da177e4SLinus Torvalds * 716477e608cSBartlomiej Zolnierkiewicz * Description: Looks up the scsi_device with the specified @lun for a given 717477e608cSBartlomiej Zolnierkiewicz * @starget. The returned scsi_device has an additional reference that 718eb44820cSRob Landley * needs to be released with scsi_device_put once you're done with it. 7191da177e4SLinus Torvalds **/ 7201da177e4SLinus Torvalds struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget, 7219cb78c16SHannes Reinecke u64 lun) 7221da177e4SLinus Torvalds { 7231da177e4SLinus Torvalds struct scsi_device *sdev; 7241da177e4SLinus Torvalds struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 7251da177e4SLinus Torvalds unsigned long flags; 7261da177e4SLinus Torvalds 7271da177e4SLinus Torvalds spin_lock_irqsave(shost->host_lock, flags); 7281da177e4SLinus Torvalds sdev = __scsi_device_lookup_by_target(starget, lun); 7291da177e4SLinus Torvalds if (sdev && scsi_device_get(sdev)) 7301da177e4SLinus Torvalds sdev = NULL; 7311da177e4SLinus Torvalds spin_unlock_irqrestore(shost->host_lock, flags); 7321da177e4SLinus Torvalds 7331da177e4SLinus Torvalds return sdev; 7341da177e4SLinus Torvalds } 7351da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_lookup_by_target); 7361da177e4SLinus Torvalds 7371da177e4SLinus Torvalds /** 738eb44820cSRob Landley * __scsi_device_lookup - find a device given the host (UNLOCKED) 7391da177e4SLinus Torvalds * @shost: SCSI host pointer 7401da177e4SLinus Torvalds * @channel: SCSI channel (zero if only one channel) 741eb44820cSRob Landley * @id: SCSI target number (physical unit number) 7421da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 7431da177e4SLinus Torvalds * 744eb44820cSRob Landley * Description: Looks up the scsi_device with the specified @channel, @id, @lun 745eb44820cSRob Landley * for a given host. The returned scsi_device does not have an additional 746eb44820cSRob Landley * reference. You must hold the host's host_lock over this call and any access 747eb44820cSRob Landley * to the returned scsi_device. 7481da177e4SLinus Torvalds * 7491da177e4SLinus Torvalds * Note: The only reason why drivers would want to use this is because 750eb44820cSRob Landley * they need to access the device list in irq context. Otherwise you 7511da177e4SLinus Torvalds * really want to use scsi_device_lookup instead. 7521da177e4SLinus Torvalds **/ 7531da177e4SLinus Torvalds struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost, 7549cb78c16SHannes Reinecke uint channel, uint id, u64 lun) 7551da177e4SLinus Torvalds { 7561da177e4SLinus Torvalds struct scsi_device *sdev; 7571da177e4SLinus Torvalds 7581da177e4SLinus Torvalds list_for_each_entry(sdev, &shost->__devices, siblings) { 7594ff7adc8SZhou Zhengping if (sdev->sdev_state == SDEV_DEL) 7604ff7adc8SZhou Zhengping continue; 7611da177e4SLinus Torvalds if (sdev->channel == channel && sdev->id == id && 7621da177e4SLinus Torvalds sdev->lun ==lun) 7631da177e4SLinus Torvalds return sdev; 7641da177e4SLinus Torvalds } 7651da177e4SLinus Torvalds 7661da177e4SLinus Torvalds return NULL; 7671da177e4SLinus Torvalds } 7681da177e4SLinus Torvalds EXPORT_SYMBOL(__scsi_device_lookup); 7691da177e4SLinus Torvalds 7701da177e4SLinus Torvalds /** 7711da177e4SLinus Torvalds * scsi_device_lookup - find a device given the host 7721da177e4SLinus Torvalds * @shost: SCSI host pointer 7731da177e4SLinus Torvalds * @channel: SCSI channel (zero if only one channel) 7741da177e4SLinus Torvalds * @id: SCSI target number (physical unit number) 7751da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 7761da177e4SLinus Torvalds * 777eb44820cSRob Landley * Description: Looks up the scsi_device with the specified @channel, @id, @lun 778eb44820cSRob Landley * for a given host. The returned scsi_device has an additional reference that 779eb44820cSRob Landley * needs to be released with scsi_device_put once you're done with it. 7801da177e4SLinus Torvalds **/ 7811da177e4SLinus Torvalds struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost, 7829cb78c16SHannes Reinecke uint channel, uint id, u64 lun) 7831da177e4SLinus Torvalds { 7841da177e4SLinus Torvalds struct scsi_device *sdev; 7851da177e4SLinus Torvalds unsigned long flags; 7861da177e4SLinus Torvalds 7871da177e4SLinus Torvalds spin_lock_irqsave(shost->host_lock, flags); 7881da177e4SLinus Torvalds sdev = __scsi_device_lookup(shost, channel, id, lun); 7891da177e4SLinus Torvalds if (sdev && scsi_device_get(sdev)) 7901da177e4SLinus Torvalds sdev = NULL; 7911da177e4SLinus Torvalds spin_unlock_irqrestore(shost->host_lock, flags); 7921da177e4SLinus Torvalds 7931da177e4SLinus Torvalds return sdev; 7941da177e4SLinus Torvalds } 7951da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_lookup); 7961da177e4SLinus Torvalds 7971da177e4SLinus Torvalds MODULE_DESCRIPTION("SCSI core"); 7981da177e4SLinus Torvalds MODULE_LICENSE("GPL"); 7991da177e4SLinus Torvalds 8001da177e4SLinus Torvalds module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR); 8011da177e4SLinus Torvalds MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels"); 8021da177e4SLinus Torvalds 803cbe7dfa2SChristoph Hellwig #ifdef CONFIG_SCSI_MQ_DEFAULT 80424c20f10SChristoph Hellwig bool scsi_use_blk_mq = true; 805cbe7dfa2SChristoph Hellwig #else 806cbe7dfa2SChristoph Hellwig bool scsi_use_blk_mq = false; 807cbe7dfa2SChristoph Hellwig #endif 808d285203cSChristoph Hellwig module_param_named(use_blk_mq, scsi_use_blk_mq, bool, S_IWUSR | S_IRUGO); 809d285203cSChristoph Hellwig 8101da177e4SLinus Torvalds static int __init init_scsi(void) 8111da177e4SLinus Torvalds { 8129bf09c23SJens Axboe int error; 8131da177e4SLinus Torvalds 8141da177e4SLinus Torvalds error = scsi_init_queue(); 8151da177e4SLinus Torvalds if (error) 8161da177e4SLinus Torvalds return error; 8171da177e4SLinus Torvalds error = scsi_init_procfs(); 8181da177e4SLinus Torvalds if (error) 8191da177e4SLinus Torvalds goto cleanup_queue; 8201da177e4SLinus Torvalds error = scsi_init_devinfo(); 8211da177e4SLinus Torvalds if (error) 8221da177e4SLinus Torvalds goto cleanup_procfs; 8231da177e4SLinus Torvalds error = scsi_init_hosts(); 8241da177e4SLinus Torvalds if (error) 8251da177e4SLinus Torvalds goto cleanup_devlist; 8261da177e4SLinus Torvalds error = scsi_init_sysctl(); 8271da177e4SLinus Torvalds if (error) 8281da177e4SLinus Torvalds goto cleanup_hosts; 8291da177e4SLinus Torvalds error = scsi_sysfs_register(); 8301da177e4SLinus Torvalds if (error) 8311da177e4SLinus Torvalds goto cleanup_sysctl; 8321da177e4SLinus Torvalds 83384314fd4SJames Smart scsi_netlink_init(); 83484314fd4SJames Smart 8351da177e4SLinus Torvalds printk(KERN_NOTICE "SCSI subsystem initialized\n"); 8361da177e4SLinus Torvalds return 0; 8371da177e4SLinus Torvalds 8381da177e4SLinus Torvalds cleanup_sysctl: 8391da177e4SLinus Torvalds scsi_exit_sysctl(); 8401da177e4SLinus Torvalds cleanup_hosts: 8411da177e4SLinus Torvalds scsi_exit_hosts(); 8421da177e4SLinus Torvalds cleanup_devlist: 8431da177e4SLinus Torvalds scsi_exit_devinfo(); 8441da177e4SLinus Torvalds cleanup_procfs: 8451da177e4SLinus Torvalds scsi_exit_procfs(); 8461da177e4SLinus Torvalds cleanup_queue: 8471da177e4SLinus Torvalds scsi_exit_queue(); 8481da177e4SLinus Torvalds printk(KERN_ERR "SCSI subsystem failed to initialize, error = %d\n", 8491da177e4SLinus Torvalds -error); 8501da177e4SLinus Torvalds return error; 8511da177e4SLinus Torvalds } 8521da177e4SLinus Torvalds 8531da177e4SLinus Torvalds static void __exit exit_scsi(void) 8541da177e4SLinus Torvalds { 85584314fd4SJames Smart scsi_netlink_exit(); 8561da177e4SLinus Torvalds scsi_sysfs_unregister(); 8571da177e4SLinus Torvalds scsi_exit_sysctl(); 8581da177e4SLinus Torvalds scsi_exit_hosts(); 8591da177e4SLinus Torvalds scsi_exit_devinfo(); 8601da177e4SLinus Torvalds scsi_exit_procfs(); 8611da177e4SLinus Torvalds scsi_exit_queue(); 862a4683487SDan Williams async_unregister_domain(&scsi_sd_probe_domain); 8631da177e4SLinus Torvalds } 8641da177e4SLinus Torvalds 8651da177e4SLinus Torvalds subsys_initcall(init_scsi); 8661da177e4SLinus Torvalds module_exit(exit_scsi); 867