2005-04-17 06:20:36 +08:00
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/*
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* scsi.c Copyright (C) 1992 Drew Eckhardt
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* Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
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* Copyright (C) 2002, 2003 Christoph Hellwig
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*
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* generic mid-level SCSI driver
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* Initial versions: Drew Eckhardt
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* Subsequent revisions: Eric Youngdale
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*
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* <drew@colorado.edu>
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*
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* Bug correction thanks go to :
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* Rik Faith <faith@cs.unc.edu>
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* Tommy Thorn <tthorn>
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* Thomas Wuensche <tw@fgb1.fgb.mw.tu-muenchen.de>
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*
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* Modified by Eric Youngdale eric@andante.org or ericy@gnu.ai.mit.edu to
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* add scatter-gather, multiple outstanding request, and other
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* enhancements.
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*
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* Native multichannel, wide scsi, /proc/scsi and hot plugging
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* support added by Michael Neuffer <mike@i-connect.net>
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*
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* Added request_module("scsi_hostadapter") for kerneld:
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* (Put an "alias scsi_hostadapter your_hostadapter" in /etc/modprobe.conf)
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* Bjorn Ekwall <bj0rn@blox.se>
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* (changed to kmod)
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*
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* Major improvements to the timeout, abort, and reset processing,
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* as well as performance modifications for large queue depths by
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* Leonard N. Zubkoff <lnz@dandelion.com>
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*
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* Converted cli() code to spinlocks, Ingo Molnar
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*
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* Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli
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*
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* out_of_space hacks, D. Gilbert (dpg) 990608
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*/
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#include <linux/module.h>
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#include <linux/moduleparam.h>
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#include <linux/kernel.h>
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#include <linux/sched.h>
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#include <linux/timer.h>
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#include <linux/string.h>
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#include <linux/slab.h>
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#include <linux/blkdev.h>
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#include <linux/delay.h>
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#include <linux/init.h>
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#include <linux/completion.h>
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#include <linux/devfs_fs_kernel.h>
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#include <linux/unistd.h>
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#include <linux/spinlock.h>
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#include <linux/kmod.h>
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#include <linux/interrupt.h>
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#include <linux/notifier.h>
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#include <linux/cpu.h>
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#include <scsi/scsi.h>
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#include <scsi/scsi_cmnd.h>
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#include <scsi/scsi_dbg.h>
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#include <scsi/scsi_device.h>
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#include <scsi/scsi_eh.h>
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#include <scsi/scsi_host.h>
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#include <scsi/scsi_tcq.h>
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#include <scsi/scsi_request.h>
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#include "scsi_priv.h"
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#include "scsi_logging.h"
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/*
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* Definitions and constants.
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*/
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#define MIN_RESET_DELAY (2*HZ)
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/* Do not call reset on error if we just did a reset within 15 sec. */
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#define MIN_RESET_PERIOD (15*HZ)
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/*
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* Macro to determine the size of SCSI command. This macro takes vendor
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* unique commands into account. SCSI commands in groups 6 and 7 are
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* vendor unique and we will depend upon the command length being
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* supplied correctly in cmd_len.
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*/
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#define CDB_SIZE(cmd) (((((cmd)->cmnd[0] >> 5) & 7) < 6) ? \
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COMMAND_SIZE((cmd)->cmnd[0]) : (cmd)->cmd_len)
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/*
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* Note - the initial logging level can be set here to log events at boot time.
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* After the system is up, you may enable logging via the /proc interface.
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*/
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unsigned int scsi_logging_level;
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#if defined(CONFIG_SCSI_LOGGING)
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EXPORT_SYMBOL(scsi_logging_level);
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#endif
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const char *const scsi_device_types[MAX_SCSI_DEVICE_CODE] = {
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"Direct-Access ",
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"Sequential-Access",
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"Printer ",
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"Processor ",
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"WORM ",
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"CD-ROM ",
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"Scanner ",
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"Optical Device ",
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"Medium Changer ",
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"Communications ",
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"Unknown ",
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"Unknown ",
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"RAID ",
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"Enclosure ",
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};
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EXPORT_SYMBOL(scsi_device_types);
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/*
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* Function: scsi_allocate_request
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*
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* Purpose: Allocate a request descriptor.
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*
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* Arguments: device - device for which we want a request
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* gfp_mask - allocation flags passed to kmalloc
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*
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* Lock status: No locks assumed to be held. This function is SMP-safe.
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*
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* Returns: Pointer to request block.
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*/
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struct scsi_request *scsi_allocate_request(struct scsi_device *sdev,
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int gfp_mask)
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{
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const int offset = ALIGN(sizeof(struct scsi_request), 4);
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const int size = offset + sizeof(struct request);
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struct scsi_request *sreq;
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sreq = kmalloc(size, gfp_mask);
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if (likely(sreq != NULL)) {
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memset(sreq, 0, size);
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sreq->sr_request = (struct request *)(((char *)sreq) + offset);
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sreq->sr_device = sdev;
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sreq->sr_host = sdev->host;
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sreq->sr_magic = SCSI_REQ_MAGIC;
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sreq->sr_data_direction = DMA_BIDIRECTIONAL;
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}
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return sreq;
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}
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EXPORT_SYMBOL(scsi_allocate_request);
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void __scsi_release_request(struct scsi_request *sreq)
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{
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struct request *req = sreq->sr_request;
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/* unlikely because the tag was usually ended earlier by the
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* mid-layer. However, for layering reasons ULD's don't end
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* the tag of commands they generate. */
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if (unlikely(blk_rq_tagged(req))) {
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unsigned long flags;
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struct request_queue *q = req->q;
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spin_lock_irqsave(q->queue_lock, flags);
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blk_queue_end_tag(q, req);
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spin_unlock_irqrestore(q->queue_lock, flags);
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}
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if (likely(sreq->sr_command != NULL)) {
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struct scsi_cmnd *cmd = sreq->sr_command;
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sreq->sr_command = NULL;
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scsi_next_command(cmd);
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}
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}
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/*
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* Function: scsi_release_request
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*
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* Purpose: Release a request descriptor.
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*
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* Arguments: sreq - request to release
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*
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* Lock status: No locks assumed to be held. This function is SMP-safe.
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*/
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void scsi_release_request(struct scsi_request *sreq)
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{
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__scsi_release_request(sreq);
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kfree(sreq);
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}
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EXPORT_SYMBOL(scsi_release_request);
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struct scsi_host_cmd_pool {
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kmem_cache_t *slab;
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unsigned int users;
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char *name;
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unsigned int slab_flags;
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unsigned int gfp_mask;
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};
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static struct scsi_host_cmd_pool scsi_cmd_pool = {
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.name = "scsi_cmd_cache",
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.slab_flags = SLAB_HWCACHE_ALIGN,
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};
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static struct scsi_host_cmd_pool scsi_cmd_dma_pool = {
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.name = "scsi_cmd_cache(DMA)",
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.slab_flags = SLAB_HWCACHE_ALIGN|SLAB_CACHE_DMA,
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.gfp_mask = __GFP_DMA,
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};
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static DECLARE_MUTEX(host_cmd_pool_mutex);
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static struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost,
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int gfp_mask)
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{
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struct scsi_cmnd *cmd;
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cmd = kmem_cache_alloc(shost->cmd_pool->slab,
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gfp_mask | shost->cmd_pool->gfp_mask);
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if (unlikely(!cmd)) {
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unsigned long flags;
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spin_lock_irqsave(&shost->free_list_lock, flags);
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if (likely(!list_empty(&shost->free_list))) {
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cmd = list_entry(shost->free_list.next,
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struct scsi_cmnd, list);
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list_del_init(&cmd->list);
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}
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spin_unlock_irqrestore(&shost->free_list_lock, flags);
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}
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return cmd;
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}
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/*
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* Function: scsi_get_command()
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*
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* Purpose: Allocate and setup a scsi command block
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*
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* Arguments: dev - parent scsi device
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* gfp_mask- allocator flags
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*
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* Returns: The allocated scsi command structure.
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*/
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struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, int gfp_mask)
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{
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struct scsi_cmnd *cmd;
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/* Bail if we can't get a reference to the device */
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if (!get_device(&dev->sdev_gendev))
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return NULL;
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cmd = __scsi_get_command(dev->host, gfp_mask);
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if (likely(cmd != NULL)) {
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unsigned long flags;
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memset(cmd, 0, sizeof(*cmd));
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cmd->device = dev;
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cmd->state = SCSI_STATE_UNUSED;
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cmd->owner = SCSI_OWNER_NOBODY;
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init_timer(&cmd->eh_timeout);
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INIT_LIST_HEAD(&cmd->list);
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spin_lock_irqsave(&dev->list_lock, flags);
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list_add_tail(&cmd->list, &dev->cmd_list);
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spin_unlock_irqrestore(&dev->list_lock, flags);
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} else
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put_device(&dev->sdev_gendev);
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return cmd;
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}
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EXPORT_SYMBOL(scsi_get_command);
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/*
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* Function: scsi_put_command()
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*
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* Purpose: Free a scsi command block
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*
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* Arguments: cmd - command block to free
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*
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* Returns: Nothing.
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*
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* Notes: The command must not belong to any lists.
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*/
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void scsi_put_command(struct scsi_cmnd *cmd)
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{
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struct scsi_device *sdev = cmd->device;
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struct Scsi_Host *shost = sdev->host;
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unsigned long flags;
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/* serious error if the command hasn't come from a device list */
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spin_lock_irqsave(&cmd->device->list_lock, flags);
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BUG_ON(list_empty(&cmd->list));
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list_del_init(&cmd->list);
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spin_unlock(&cmd->device->list_lock);
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/* changing locks here, don't need to restore the irq state */
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spin_lock(&shost->free_list_lock);
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if (unlikely(list_empty(&shost->free_list))) {
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list_add(&cmd->list, &shost->free_list);
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cmd = NULL;
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}
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spin_unlock_irqrestore(&shost->free_list_lock, flags);
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if (likely(cmd != NULL))
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kmem_cache_free(shost->cmd_pool->slab, cmd);
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put_device(&sdev->sdev_gendev);
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}
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EXPORT_SYMBOL(scsi_put_command);
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/*
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* Function: scsi_setup_command_freelist()
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*
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* Purpose: Setup the command freelist for a scsi host.
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*
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* Arguments: shost - host to allocate the freelist for.
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*
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* Returns: Nothing.
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*/
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int scsi_setup_command_freelist(struct Scsi_Host *shost)
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{
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struct scsi_host_cmd_pool *pool;
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struct scsi_cmnd *cmd;
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spin_lock_init(&shost->free_list_lock);
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INIT_LIST_HEAD(&shost->free_list);
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/*
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* Select a command slab for this host and create it if not
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* yet existant.
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*/
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down(&host_cmd_pool_mutex);
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pool = (shost->unchecked_isa_dma ? &scsi_cmd_dma_pool : &scsi_cmd_pool);
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if (!pool->users) {
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pool->slab = kmem_cache_create(pool->name,
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sizeof(struct scsi_cmnd), 0,
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pool->slab_flags, NULL, NULL);
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if (!pool->slab)
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goto fail;
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}
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pool->users++;
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shost->cmd_pool = pool;
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up(&host_cmd_pool_mutex);
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/*
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* Get one backup command for this host.
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*/
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cmd = kmem_cache_alloc(shost->cmd_pool->slab,
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GFP_KERNEL | shost->cmd_pool->gfp_mask);
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if (!cmd)
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goto fail2;
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list_add(&cmd->list, &shost->free_list);
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return 0;
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fail2:
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if (!--pool->users)
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kmem_cache_destroy(pool->slab);
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return -ENOMEM;
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fail:
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up(&host_cmd_pool_mutex);
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return -ENOMEM;
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}
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/*
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* Function: scsi_destroy_command_freelist()
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*
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* Purpose: Release the command freelist for a scsi host.
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*
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* Arguments: shost - host that's freelist is going to be destroyed
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*/
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void scsi_destroy_command_freelist(struct Scsi_Host *shost)
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{
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while (!list_empty(&shost->free_list)) {
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struct scsi_cmnd *cmd;
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|
|
cmd = list_entry(shost->free_list.next, struct scsi_cmnd, list);
|
|
|
|
list_del_init(&cmd->list);
|
|
|
|
kmem_cache_free(shost->cmd_pool->slab, cmd);
|
|
|
|
}
|
|
|
|
|
|
|
|
down(&host_cmd_pool_mutex);
|
|
|
|
if (!--shost->cmd_pool->users)
|
|
|
|
kmem_cache_destroy(shost->cmd_pool->slab);
|
|
|
|
up(&host_cmd_pool_mutex);
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef CONFIG_SCSI_LOGGING
|
|
|
|
void scsi_log_send(struct scsi_cmnd *cmd)
|
|
|
|
{
|
|
|
|
unsigned int level;
|
|
|
|
struct scsi_device *sdev;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If ML QUEUE log level is greater than or equal to:
|
|
|
|
*
|
|
|
|
* 1: nothing (match completion)
|
|
|
|
*
|
|
|
|
* 2: log opcode + command of all commands
|
|
|
|
*
|
|
|
|
* 3: same as 2 plus dump cmd address
|
|
|
|
*
|
|
|
|
* 4: same as 3 plus dump extra junk
|
|
|
|
*/
|
|
|
|
if (unlikely(scsi_logging_level)) {
|
|
|
|
level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT,
|
|
|
|
SCSI_LOG_MLQUEUE_BITS);
|
|
|
|
if (level > 1) {
|
|
|
|
sdev = cmd->device;
|
|
|
|
printk(KERN_INFO "scsi <%d:%d:%d:%d> send ",
|
|
|
|
sdev->host->host_no, sdev->channel, sdev->id,
|
|
|
|
sdev->lun);
|
|
|
|
if (level > 2)
|
|
|
|
printk("0x%p ", cmd);
|
|
|
|
/*
|
|
|
|
* spaces to match disposition and cmd->result
|
|
|
|
* output in scsi_log_completion.
|
|
|
|
*/
|
|
|
|
printk(" ");
|
|
|
|
scsi_print_command(cmd);
|
|
|
|
if (level > 3) {
|
|
|
|
printk(KERN_INFO "buffer = 0x%p, bufflen = %d,"
|
|
|
|
" done = 0x%p, queuecommand 0x%p\n",
|
|
|
|
cmd->buffer, cmd->bufflen,
|
|
|
|
cmd->done,
|
|
|
|
sdev->host->hostt->queuecommand);
|
|
|
|
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void scsi_log_completion(struct scsi_cmnd *cmd, int disposition)
|
|
|
|
{
|
|
|
|
unsigned int level;
|
|
|
|
struct scsi_device *sdev;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If ML COMPLETE log level is greater than or equal to:
|
|
|
|
*
|
|
|
|
* 1: log disposition, result, opcode + command, and conditionally
|
|
|
|
* sense data for failures or non SUCCESS dispositions.
|
|
|
|
*
|
|
|
|
* 2: same as 1 but for all command completions.
|
|
|
|
*
|
|
|
|
* 3: same as 2 plus dump cmd address
|
|
|
|
*
|
|
|
|
* 4: same as 3 plus dump extra junk
|
|
|
|
*/
|
|
|
|
if (unlikely(scsi_logging_level)) {
|
|
|
|
level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT,
|
|
|
|
SCSI_LOG_MLCOMPLETE_BITS);
|
|
|
|
if (((level > 0) && (cmd->result || disposition != SUCCESS)) ||
|
|
|
|
(level > 1)) {
|
|
|
|
sdev = cmd->device;
|
|
|
|
printk(KERN_INFO "scsi <%d:%d:%d:%d> done ",
|
|
|
|
sdev->host->host_no, sdev->channel, sdev->id,
|
|
|
|
sdev->lun);
|
|
|
|
if (level > 2)
|
|
|
|
printk("0x%p ", cmd);
|
|
|
|
/*
|
|
|
|
* Dump truncated values, so we usually fit within
|
|
|
|
* 80 chars.
|
|
|
|
*/
|
|
|
|
switch (disposition) {
|
|
|
|
case SUCCESS:
|
|
|
|
printk("SUCCESS");
|
|
|
|
break;
|
|
|
|
case NEEDS_RETRY:
|
|
|
|
printk("RETRY ");
|
|
|
|
break;
|
|
|
|
case ADD_TO_MLQUEUE:
|
|
|
|
printk("MLQUEUE");
|
|
|
|
break;
|
|
|
|
case FAILED:
|
|
|
|
printk("FAILED ");
|
|
|
|
break;
|
|
|
|
case TIMEOUT_ERROR:
|
|
|
|
/*
|
|
|
|
* If called via scsi_times_out.
|
|
|
|
*/
|
|
|
|
printk("TIMEOUT");
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
printk("UNKNOWN");
|
|
|
|
}
|
|
|
|
printk(" %8x ", cmd->result);
|
|
|
|
scsi_print_command(cmd);
|
|
|
|
if (status_byte(cmd->result) & CHECK_CONDITION) {
|
|
|
|
/*
|
2005-04-04 03:53:59 +08:00
|
|
|
* XXX The scsi_print_sense formatting/prefix
|
2005-04-17 06:20:36 +08:00
|
|
|
* doesn't match this function.
|
|
|
|
*/
|
|
|
|
scsi_print_sense("", cmd);
|
|
|
|
}
|
|
|
|
if (level > 3) {
|
|
|
|
printk(KERN_INFO "scsi host busy %d failed %d\n",
|
|
|
|
sdev->host->host_busy,
|
|
|
|
sdev->host->host_failed);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Assign a serial number and pid to the request for error recovery
|
|
|
|
* and debugging purposes. Protected by the Host_Lock of host.
|
|
|
|
*/
|
|
|
|
static inline void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd *cmd)
|
|
|
|
{
|
|
|
|
cmd->serial_number = host->cmd_serial_number++;
|
|
|
|
if (cmd->serial_number == 0)
|
|
|
|
cmd->serial_number = host->cmd_serial_number++;
|
|
|
|
|
|
|
|
cmd->pid = host->cmd_pid++;
|
|
|
|
if (cmd->pid == 0)
|
|
|
|
cmd->pid = host->cmd_pid++;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Function: scsi_dispatch_command
|
|
|
|
*
|
|
|
|
* Purpose: Dispatch a command to the low-level driver.
|
|
|
|
*
|
|
|
|
* Arguments: cmd - command block we are dispatching.
|
|
|
|
*
|
|
|
|
* Notes:
|
|
|
|
*/
|
|
|
|
int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
|
|
|
|
{
|
|
|
|
struct Scsi_Host *host = cmd->device->host;
|
|
|
|
unsigned long flags = 0;
|
|
|
|
unsigned long timeout;
|
|
|
|
int rtn = 0;
|
|
|
|
|
|
|
|
/* check if the device is still usable */
|
|
|
|
if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
|
|
|
|
/* in SDEV_DEL we error all commands. DID_NO_CONNECT
|
|
|
|
* returns an immediate error upwards, and signals
|
|
|
|
* that the device is no longer present */
|
|
|
|
cmd->result = DID_NO_CONNECT << 16;
|
|
|
|
atomic_inc(&cmd->device->iorequest_cnt);
|
|
|
|
scsi_done(cmd);
|
|
|
|
/* return 0 (because the command has been processed) */
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Check to see if the scsi lld put this device into state SDEV_BLOCK. */
|
|
|
|
if (unlikely(cmd->device->sdev_state == SDEV_BLOCK)) {
|
|
|
|
/*
|
|
|
|
* in SDEV_BLOCK, the command is just put back on the device
|
|
|
|
* queue. The suspend state has already blocked the queue so
|
|
|
|
* future requests should not occur until the device
|
|
|
|
* transitions out of the suspend state.
|
|
|
|
*/
|
|
|
|
scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
|
|
|
|
|
|
|
|
SCSI_LOG_MLQUEUE(3, printk("queuecommand : device blocked \n"));
|
|
|
|
|
|
|
|
/*
|
|
|
|
* NOTE: rtn is still zero here because we don't need the
|
|
|
|
* queue to be plugged on return (it's already stopped)
|
|
|
|
*/
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If SCSI-2 or lower, store the LUN value in cmnd.
|
|
|
|
*/
|
|
|
|
if (cmd->device->scsi_level <= SCSI_2) {
|
|
|
|
cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) |
|
|
|
|
(cmd->device->lun << 5 & 0xe0);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We will wait MIN_RESET_DELAY clock ticks after the last reset so
|
|
|
|
* we can avoid the drive not being ready.
|
|
|
|
*/
|
|
|
|
timeout = host->last_reset + MIN_RESET_DELAY;
|
|
|
|
|
|
|
|
if (host->resetting && time_before(jiffies, timeout)) {
|
|
|
|
int ticks_remaining = timeout - jiffies;
|
|
|
|
/*
|
|
|
|
* NOTE: This may be executed from within an interrupt
|
|
|
|
* handler! This is bad, but for now, it'll do. The irq
|
|
|
|
* level of the interrupt handler has been masked out by the
|
|
|
|
* platform dependent interrupt handling code already, so the
|
|
|
|
* sti() here will not cause another call to the SCSI host's
|
|
|
|
* interrupt handler (assuming there is one irq-level per
|
|
|
|
* host).
|
|
|
|
*/
|
|
|
|
while (--ticks_remaining >= 0)
|
|
|
|
mdelay(1 + 999 / HZ);
|
|
|
|
host->resetting = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* AK: unlikely race here: for some reason the timer could
|
|
|
|
* expire before the serial number is set up below.
|
|
|
|
*/
|
|
|
|
scsi_add_timer(cmd, cmd->timeout_per_command, scsi_times_out);
|
|
|
|
|
|
|
|
scsi_log_send(cmd);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We will use a queued command if possible, otherwise we will
|
|
|
|
* emulate the queuing and calling of completion function ourselves.
|
|
|
|
*/
|
|
|
|
|
|
|
|
cmd->state = SCSI_STATE_QUEUED;
|
|
|
|
cmd->owner = SCSI_OWNER_LOWLEVEL;
|
|
|
|
|
|
|
|
atomic_inc(&cmd->device->iorequest_cnt);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Before we queue this command, check if the command
|
|
|
|
* length exceeds what the host adapter can handle.
|
|
|
|
*/
|
|
|
|
if (CDB_SIZE(cmd) > cmd->device->host->max_cmd_len) {
|
|
|
|
SCSI_LOG_MLQUEUE(3,
|
|
|
|
printk("queuecommand : command too long.\n"));
|
|
|
|
cmd->result = (DID_ABORT << 16);
|
|
|
|
|
|
|
|
scsi_done(cmd);
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
spin_lock_irqsave(host->host_lock, flags);
|
|
|
|
scsi_cmd_get_serial(host, cmd);
|
|
|
|
|
|
|
|
if (unlikely(test_bit(SHOST_CANCEL, &host->shost_state))) {
|
|
|
|
cmd->result = (DID_NO_CONNECT << 16);
|
|
|
|
scsi_done(cmd);
|
|
|
|
} else {
|
|
|
|
rtn = host->hostt->queuecommand(cmd, scsi_done);
|
|
|
|
}
|
|
|
|
spin_unlock_irqrestore(host->host_lock, flags);
|
|
|
|
if (rtn) {
|
|
|
|
atomic_inc(&cmd->device->iodone_cnt);
|
|
|
|
scsi_queue_insert(cmd,
|
|
|
|
(rtn == SCSI_MLQUEUE_DEVICE_BUSY) ?
|
|
|
|
rtn : SCSI_MLQUEUE_HOST_BUSY);
|
|
|
|
SCSI_LOG_MLQUEUE(3,
|
|
|
|
printk("queuecommand : request rejected\n"));
|
|
|
|
}
|
|
|
|
|
|
|
|
out:
|
|
|
|
SCSI_LOG_MLQUEUE(3, printk("leaving scsi_dispatch_cmnd()\n"));
|
|
|
|
return rtn;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Function: scsi_init_cmd_from_req
|
|
|
|
*
|
|
|
|
* Purpose: Queue a SCSI command
|
|
|
|
* Purpose: Initialize a struct scsi_cmnd from a struct scsi_request
|
|
|
|
*
|
|
|
|
* Arguments: cmd - command descriptor.
|
|
|
|
* sreq - Request from the queue.
|
|
|
|
*
|
|
|
|
* Lock status: None needed.
|
|
|
|
*
|
|
|
|
* Returns: Nothing.
|
|
|
|
*
|
|
|
|
* Notes: Mainly transfer data from the request structure to the
|
|
|
|
* command structure. The request structure is allocated
|
|
|
|
* using the normal memory allocator, and requests can pile
|
|
|
|
* up to more or less any depth. The command structure represents
|
|
|
|
* a consumable resource, as these are allocated into a pool
|
|
|
|
* when the SCSI subsystem initializes. The preallocation is
|
|
|
|
* required so that in low-memory situations a disk I/O request
|
|
|
|
* won't cause the memory manager to try and write out a page.
|
|
|
|
* The request structure is generally used by ioctls and character
|
|
|
|
* devices.
|
|
|
|
*/
|
|
|
|
void scsi_init_cmd_from_req(struct scsi_cmnd *cmd, struct scsi_request *sreq)
|
|
|
|
{
|
|
|
|
sreq->sr_command = cmd;
|
|
|
|
|
|
|
|
cmd->owner = SCSI_OWNER_MIDLEVEL;
|
|
|
|
cmd->cmd_len = sreq->sr_cmd_len;
|
|
|
|
cmd->use_sg = sreq->sr_use_sg;
|
|
|
|
|
|
|
|
cmd->request = sreq->sr_request;
|
|
|
|
memcpy(cmd->data_cmnd, sreq->sr_cmnd, sizeof(cmd->data_cmnd));
|
|
|
|
cmd->serial_number = 0;
|
|
|
|
cmd->bufflen = sreq->sr_bufflen;
|
|
|
|
cmd->buffer = sreq->sr_buffer;
|
|
|
|
cmd->retries = 0;
|
|
|
|
cmd->allowed = sreq->sr_allowed;
|
|
|
|
cmd->done = sreq->sr_done;
|
|
|
|
cmd->timeout_per_command = sreq->sr_timeout_per_command;
|
|
|
|
cmd->sc_data_direction = sreq->sr_data_direction;
|
|
|
|
cmd->sglist_len = sreq->sr_sglist_len;
|
|
|
|
cmd->underflow = sreq->sr_underflow;
|
|
|
|
cmd->sc_request = sreq;
|
|
|
|
memcpy(cmd->cmnd, sreq->sr_cmnd, sizeof(sreq->sr_cmnd));
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Zero the sense buffer. Some host adapters automatically request
|
|
|
|
* sense on error. 0 is not a valid sense code.
|
|
|
|
*/
|
|
|
|
memset(cmd->sense_buffer, 0, sizeof(sreq->sr_sense_buffer));
|
|
|
|
cmd->request_buffer = sreq->sr_buffer;
|
|
|
|
cmd->request_bufflen = sreq->sr_bufflen;
|
|
|
|
cmd->old_use_sg = cmd->use_sg;
|
|
|
|
if (cmd->cmd_len == 0)
|
|
|
|
cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]);
|
|
|
|
cmd->old_cmd_len = cmd->cmd_len;
|
|
|
|
cmd->sc_old_data_direction = cmd->sc_data_direction;
|
|
|
|
cmd->old_underflow = cmd->underflow;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Start the timer ticking.
|
|
|
|
*/
|
|
|
|
cmd->abort_reason = 0;
|
|
|
|
cmd->result = 0;
|
|
|
|
|
|
|
|
SCSI_LOG_MLQUEUE(3, printk("Leaving scsi_init_cmd_from_req()\n"));
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Per-CPU I/O completion queue.
|
|
|
|
*/
|
|
|
|
static DEFINE_PER_CPU(struct list_head, scsi_done_q);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* scsi_done - Enqueue the finished SCSI command into the done queue.
|
|
|
|
* @cmd: The SCSI Command for which a low-level device driver (LLDD) gives
|
|
|
|
* ownership back to SCSI Core -- i.e. the LLDD has finished with it.
|
|
|
|
*
|
|
|
|
* This function is the mid-level's (SCSI Core) interrupt routine, which
|
|
|
|
* regains ownership of the SCSI command (de facto) from a LLDD, and enqueues
|
|
|
|
* the command to the done queue for further processing.
|
|
|
|
*
|
|
|
|
* This is the producer of the done queue who enqueues at the tail.
|
|
|
|
*
|
|
|
|
* This function is interrupt context safe.
|
|
|
|
*/
|
|
|
|
void scsi_done(struct scsi_cmnd *cmd)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* We don't have to worry about this one timing out any more.
|
|
|
|
* If we are unable to remove the timer, then the command
|
|
|
|
* has already timed out. In which case, we have no choice but to
|
|
|
|
* let the timeout function run, as we have no idea where in fact
|
|
|
|
* that function could really be. It might be on another processor,
|
|
|
|
* etc, etc.
|
|
|
|
*/
|
|
|
|
if (!scsi_delete_timer(cmd))
|
|
|
|
return;
|
|
|
|
__scsi_done(cmd);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Private entry to scsi_done() to complete a command when the timer
|
|
|
|
* isn't running --- used by scsi_times_out */
|
|
|
|
void __scsi_done(struct scsi_cmnd *cmd)
|
|
|
|
{
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Set the serial numbers back to zero
|
|
|
|
*/
|
|
|
|
cmd->serial_number = 0;
|
|
|
|
cmd->state = SCSI_STATE_BHQUEUE;
|
|
|
|
cmd->owner = SCSI_OWNER_BH_HANDLER;
|
|
|
|
|
|
|
|
atomic_inc(&cmd->device->iodone_cnt);
|
|
|
|
if (cmd->result)
|
|
|
|
atomic_inc(&cmd->device->ioerr_cnt);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Next, enqueue the command into the done queue.
|
|
|
|
* It is a per-CPU queue, so we just disable local interrupts
|
|
|
|
* and need no spinlock.
|
|
|
|
*/
|
|
|
|
local_irq_save(flags);
|
|
|
|
list_add_tail(&cmd->eh_entry, &__get_cpu_var(scsi_done_q));
|
|
|
|
raise_softirq_irqoff(SCSI_SOFTIRQ);
|
|
|
|
local_irq_restore(flags);
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* scsi_softirq - Perform post-interrupt processing of finished SCSI commands.
|
|
|
|
*
|
|
|
|
* This is the consumer of the done queue.
|
|
|
|
*
|
|
|
|
* This is called with all interrupts enabled. This should reduce
|
|
|
|
* interrupt latency, stack depth, and reentrancy of the low-level
|
|
|
|
* drivers.
|
|
|
|
*/
|
|
|
|
static void scsi_softirq(struct softirq_action *h)
|
|
|
|
{
|
|
|
|
int disposition;
|
|
|
|
LIST_HEAD(local_q);
|
|
|
|
|
|
|
|
local_irq_disable();
|
|
|
|
list_splice_init(&__get_cpu_var(scsi_done_q), &local_q);
|
|
|
|
local_irq_enable();
|
|
|
|
|
|
|
|
while (!list_empty(&local_q)) {
|
|
|
|
struct scsi_cmnd *cmd = list_entry(local_q.next,
|
|
|
|
struct scsi_cmnd, eh_entry);
|
|
|
|
list_del_init(&cmd->eh_entry);
|
|
|
|
|
|
|
|
disposition = scsi_decide_disposition(cmd);
|
|
|
|
scsi_log_completion(cmd, disposition);
|
|
|
|
switch (disposition) {
|
|
|
|
case SUCCESS:
|
|
|
|
scsi_finish_command(cmd);
|
|
|
|
break;
|
|
|
|
case NEEDS_RETRY:
|
|
|
|
scsi_retry_command(cmd);
|
|
|
|
break;
|
|
|
|
case ADD_TO_MLQUEUE:
|
|
|
|
scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
if (!scsi_eh_scmd_add(cmd, 0))
|
|
|
|
scsi_finish_command(cmd);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Function: scsi_retry_command
|
|
|
|
*
|
|
|
|
* Purpose: Send a command back to the low level to be retried.
|
|
|
|
*
|
|
|
|
* Notes: This command is always executed in the context of the
|
|
|
|
* bottom half handler, or the error handler thread. Low
|
|
|
|
* level drivers should not become re-entrant as a result of
|
|
|
|
* this.
|
|
|
|
*/
|
|
|
|
int scsi_retry_command(struct scsi_cmnd *cmd)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* Restore the SCSI command state.
|
|
|
|
*/
|
|
|
|
scsi_setup_cmd_retry(cmd);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Zero the sense information from the last time we tried
|
|
|
|
* this command.
|
|
|
|
*/
|
|
|
|
memset(cmd->sense_buffer, 0, sizeof(cmd->sense_buffer));
|
|
|
|
|
|
|
|
return scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY);
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Function: scsi_finish_command
|
|
|
|
*
|
|
|
|
* Purpose: Pass command off to upper layer for finishing of I/O
|
|
|
|
* request, waking processes that are waiting on results,
|
|
|
|
* etc.
|
|
|
|
*/
|
|
|
|
void scsi_finish_command(struct scsi_cmnd *cmd)
|
|
|
|
{
|
|
|
|
struct scsi_device *sdev = cmd->device;
|
|
|
|
struct Scsi_Host *shost = sdev->host;
|
|
|
|
struct scsi_request *sreq;
|
|
|
|
|
|
|
|
scsi_device_unbusy(sdev);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Clear the flags which say that the device/host is no longer
|
|
|
|
* capable of accepting new commands. These are set in scsi_queue.c
|
|
|
|
* for both the queue full condition on a device, and for a
|
|
|
|
* host full condition on the host.
|
|
|
|
*
|
|
|
|
* XXX(hch): What about locking?
|
|
|
|
*/
|
|
|
|
shost->host_blocked = 0;
|
|
|
|
sdev->device_blocked = 0;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If we have valid sense information, then some kind of recovery
|
|
|
|
* must have taken place. Make a note of this.
|
|
|
|
*/
|
|
|
|
if (SCSI_SENSE_VALID(cmd))
|
|
|
|
cmd->result |= (DRIVER_SENSE << 24);
|
|
|
|
|
|
|
|
SCSI_LOG_MLCOMPLETE(4, printk("Notifying upper driver of completion "
|
|
|
|
"for device %d %x\n", sdev->id, cmd->result));
|
|
|
|
|
|
|
|
cmd->owner = SCSI_OWNER_HIGHLEVEL;
|
|
|
|
cmd->state = SCSI_STATE_FINISHED;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We can get here with use_sg=0, causing a panic in the upper level
|
|
|
|
*/
|
|
|
|
cmd->use_sg = cmd->old_use_sg;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If there is an associated request structure, copy the data over
|
|
|
|
* before we call the completion function.
|
|
|
|
*/
|
|
|
|
sreq = cmd->sc_request;
|
|
|
|
if (sreq) {
|
|
|
|
sreq->sr_result = sreq->sr_command->result;
|
|
|
|
if (sreq->sr_result) {
|
|
|
|
memcpy(sreq->sr_sense_buffer,
|
|
|
|
sreq->sr_command->sense_buffer,
|
|
|
|
sizeof(sreq->sr_sense_buffer));
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
cmd->done(cmd);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(scsi_finish_command);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Function: scsi_adjust_queue_depth()
|
|
|
|
*
|
|
|
|
* Purpose: Allow low level drivers to tell us to change the queue depth
|
|
|
|
* on a specific SCSI device
|
|
|
|
*
|
|
|
|
* Arguments: sdev - SCSI Device in question
|
|
|
|
* tagged - Do we use tagged queueing (non-0) or do we treat
|
|
|
|
* this device as an untagged device (0)
|
|
|
|
* tags - Number of tags allowed if tagged queueing enabled,
|
|
|
|
* or number of commands the low level driver can
|
|
|
|
* queue up in non-tagged mode (as per cmd_per_lun).
|
|
|
|
*
|
|
|
|
* Returns: Nothing
|
|
|
|
*
|
|
|
|
* Lock Status: None held on entry
|
|
|
|
*
|
|
|
|
* Notes: Low level drivers may call this at any time and we will do
|
|
|
|
* the right thing depending on whether or not the device is
|
|
|
|
* currently active and whether or not it even has the
|
|
|
|
* command blocks built yet.
|
|
|
|
*/
|
|
|
|
void scsi_adjust_queue_depth(struct scsi_device *sdev, int tagged, int tags)
|
|
|
|
{
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* refuse to set tagged depth to an unworkable size
|
|
|
|
*/
|
|
|
|
if (tags <= 0)
|
|
|
|
return;
|
|
|
|
|
|
|
|
spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
|
|
|
|
|
|
|
|
/* Check to see if the queue is managed by the block layer
|
|
|
|
* if it is, and we fail to adjust the depth, exit */
|
|
|
|
if (blk_queue_tagged(sdev->request_queue) &&
|
|
|
|
blk_queue_resize_tags(sdev->request_queue, tags) != 0)
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
sdev->queue_depth = tags;
|
|
|
|
switch (tagged) {
|
|
|
|
case MSG_ORDERED_TAG:
|
|
|
|
sdev->ordered_tags = 1;
|
|
|
|
sdev->simple_tags = 1;
|
|
|
|
break;
|
|
|
|
case MSG_SIMPLE_TAG:
|
|
|
|
sdev->ordered_tags = 0;
|
|
|
|
sdev->simple_tags = 1;
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
printk(KERN_WARNING "(scsi%d:%d:%d:%d) "
|
|
|
|
"scsi_adjust_queue_depth, bad queue type, "
|
|
|
|
"disabled\n", sdev->host->host_no,
|
|
|
|
sdev->channel, sdev->id, sdev->lun);
|
|
|
|
case 0:
|
|
|
|
sdev->ordered_tags = sdev->simple_tags = 0;
|
|
|
|
sdev->queue_depth = tags;
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
out:
|
|
|
|
spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(scsi_adjust_queue_depth);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Function: scsi_track_queue_full()
|
|
|
|
*
|
|
|
|
* Purpose: This function will track successive QUEUE_FULL events on a
|
|
|
|
* specific SCSI device to determine if and when there is a
|
|
|
|
* need to adjust the queue depth on the device.
|
|
|
|
*
|
|
|
|
* Arguments: sdev - SCSI Device in question
|
|
|
|
* depth - Current number of outstanding SCSI commands on
|
|
|
|
* this device, not counting the one returned as
|
|
|
|
* QUEUE_FULL.
|
|
|
|
*
|
|
|
|
* Returns: 0 - No change needed
|
|
|
|
* >0 - Adjust queue depth to this new depth
|
|
|
|
* -1 - Drop back to untagged operation using host->cmd_per_lun
|
|
|
|
* as the untagged command depth
|
|
|
|
*
|
|
|
|
* Lock Status: None held on entry
|
|
|
|
*
|
|
|
|
* Notes: Low level drivers may call this at any time and we will do
|
|
|
|
* "The Right Thing." We are interrupt context safe.
|
|
|
|
*/
|
|
|
|
int scsi_track_queue_full(struct scsi_device *sdev, int depth)
|
|
|
|
{
|
|
|
|
if ((jiffies >> 4) == sdev->last_queue_full_time)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
sdev->last_queue_full_time = (jiffies >> 4);
|
|
|
|
if (sdev->last_queue_full_depth != depth) {
|
|
|
|
sdev->last_queue_full_count = 1;
|
|
|
|
sdev->last_queue_full_depth = depth;
|
|
|
|
} else {
|
|
|
|
sdev->last_queue_full_count++;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (sdev->last_queue_full_count <= 10)
|
|
|
|
return 0;
|
|
|
|
if (sdev->last_queue_full_depth < 8) {
|
|
|
|
/* Drop back to untagged */
|
|
|
|
scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
|
|
|
|
return -1;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (sdev->ordered_tags)
|
|
|
|
scsi_adjust_queue_depth(sdev, MSG_ORDERED_TAG, depth);
|
|
|
|
else
|
|
|
|
scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
|
|
|
|
return depth;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(scsi_track_queue_full);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* scsi_device_get - get an addition reference to a scsi_device
|
|
|
|
* @sdev: device to get a reference to
|
|
|
|
*
|
|
|
|
* Gets a reference to the scsi_device and increments the use count
|
|
|
|
* of the underlying LLDD module. You must hold host_lock of the
|
|
|
|
* parent Scsi_Host or already have a reference when calling this.
|
|
|
|
*/
|
|
|
|
int scsi_device_get(struct scsi_device *sdev)
|
|
|
|
{
|
|
|
|
if (sdev->sdev_state == SDEV_DEL || sdev->sdev_state == SDEV_CANCEL)
|
|
|
|
return -ENXIO;
|
|
|
|
if (!get_device(&sdev->sdev_gendev))
|
|
|
|
return -ENXIO;
|
|
|
|
if (!try_module_get(sdev->host->hostt->module)) {
|
|
|
|
put_device(&sdev->sdev_gendev);
|
|
|
|
return -ENXIO;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(scsi_device_get);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* scsi_device_put - release a reference to a scsi_device
|
|
|
|
* @sdev: device to release a reference on.
|
|
|
|
*
|
|
|
|
* Release a reference to the scsi_device and decrements the use count
|
|
|
|
* of the underlying LLDD module. The device is freed once the last
|
|
|
|
* user vanishes.
|
|
|
|
*/
|
|
|
|
void scsi_device_put(struct scsi_device *sdev)
|
|
|
|
{
|
|
|
|
module_put(sdev->host->hostt->module);
|
|
|
|
put_device(&sdev->sdev_gendev);
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(scsi_device_put);
|
|
|
|
|
|
|
|
/* helper for shost_for_each_device, thus not documented */
|
|
|
|
struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost,
|
|
|
|
struct scsi_device *prev)
|
|
|
|
{
|
|
|
|
struct list_head *list = (prev ? &prev->siblings : &shost->__devices);
|
|
|
|
struct scsi_device *next = NULL;
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
spin_lock_irqsave(shost->host_lock, flags);
|
|
|
|
while (list->next != &shost->__devices) {
|
|
|
|
next = list_entry(list->next, struct scsi_device, siblings);
|
|
|
|
/* skip devices that we can't get a reference to */
|
|
|
|
if (!scsi_device_get(next))
|
|
|
|
break;
|
|
|
|
next = NULL;
|
|
|
|
list = list->next;
|
|
|
|
}
|
|
|
|
spin_unlock_irqrestore(shost->host_lock, flags);
|
|
|
|
|
|
|
|
if (prev)
|
|
|
|
scsi_device_put(prev);
|
|
|
|
return next;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(__scsi_iterate_devices);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* starget_for_each_device - helper to walk all devices of a target
|
|
|
|
* @starget: target whose devices we want to iterate over.
|
|
|
|
*
|
|
|
|
* This traverses over each devices of @shost. The devices have
|
|
|
|
* a reference that must be released by scsi_host_put when breaking
|
|
|
|
* out of the loop.
|
|
|
|
*/
|
|
|
|
void starget_for_each_device(struct scsi_target *starget, void * data,
|
|
|
|
void (*fn)(struct scsi_device *, void *))
|
|
|
|
{
|
|
|
|
struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
|
|
|
|
struct scsi_device *sdev;
|
|
|
|
|
|
|
|
shost_for_each_device(sdev, shost) {
|
|
|
|
if ((sdev->channel == starget->channel) &&
|
|
|
|
(sdev->id == starget->id))
|
|
|
|
fn(sdev, data);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(starget_for_each_device);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* __scsi_device_lookup_by_target - find a device given the target (UNLOCKED)
|
|
|
|
* @starget: SCSI target pointer
|
|
|
|
* @lun: SCSI Logical Unit Number
|
|
|
|
*
|
|
|
|
* Looks up the scsi_device with the specified @lun for a give
|
|
|
|
* @starget. The returned scsi_device does not have an additional
|
|
|
|
* reference. You must hold the host's host_lock over this call and
|
|
|
|
* any access to the returned scsi_device.
|
|
|
|
*
|
|
|
|
* Note: The only reason why drivers would want to use this is because
|
|
|
|
* they're need to access the device list in irq context. Otherwise you
|
|
|
|
* really want to use scsi_device_lookup_by_target instead.
|
|
|
|
**/
|
|
|
|
struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget,
|
|
|
|
uint lun)
|
|
|
|
{
|
|
|
|
struct scsi_device *sdev;
|
|
|
|
|
|
|
|
list_for_each_entry(sdev, &starget->devices, same_target_siblings) {
|
|
|
|
if (sdev->lun ==lun)
|
|
|
|
return sdev;
|
|
|
|
}
|
|
|
|
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(__scsi_device_lookup_by_target);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* scsi_device_lookup_by_target - find a device given the target
|
|
|
|
* @starget: SCSI target pointer
|
|
|
|
* @lun: SCSI Logical Unit Number
|
|
|
|
*
|
|
|
|
* Looks up the scsi_device with the specified @channel, @id, @lun for a
|
|
|
|
* give host. The returned scsi_device has an additional reference that
|
|
|
|
* needs to be release with scsi_host_put once you're done with it.
|
|
|
|
**/
|
|
|
|
struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget,
|
|
|
|
uint lun)
|
|
|
|
{
|
|
|
|
struct scsi_device *sdev;
|
|
|
|
struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
spin_lock_irqsave(shost->host_lock, flags);
|
|
|
|
sdev = __scsi_device_lookup_by_target(starget, lun);
|
|
|
|
if (sdev && scsi_device_get(sdev))
|
|
|
|
sdev = NULL;
|
|
|
|
spin_unlock_irqrestore(shost->host_lock, flags);
|
|
|
|
|
|
|
|
return sdev;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(scsi_device_lookup_by_target);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* scsi_device_lookup - find a device given the host (UNLOCKED)
|
|
|
|
* @shost: SCSI host pointer
|
|
|
|
* @channel: SCSI channel (zero if only one channel)
|
|
|
|
* @pun: SCSI target number (physical unit number)
|
|
|
|
* @lun: SCSI Logical Unit Number
|
|
|
|
*
|
|
|
|
* Looks up the scsi_device with the specified @channel, @id, @lun for a
|
|
|
|
* give host. The returned scsi_device does not have an additional reference.
|
|
|
|
* You must hold the host's host_lock over this call and any access to the
|
|
|
|
* returned scsi_device.
|
|
|
|
*
|
|
|
|
* Note: The only reason why drivers would want to use this is because
|
|
|
|
* they're need to access the device list in irq context. Otherwise you
|
|
|
|
* really want to use scsi_device_lookup instead.
|
|
|
|
**/
|
|
|
|
struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost,
|
|
|
|
uint channel, uint id, uint lun)
|
|
|
|
{
|
|
|
|
struct scsi_device *sdev;
|
|
|
|
|
|
|
|
list_for_each_entry(sdev, &shost->__devices, siblings) {
|
|
|
|
if (sdev->channel == channel && sdev->id == id &&
|
|
|
|
sdev->lun ==lun)
|
|
|
|
return sdev;
|
|
|
|
}
|
|
|
|
|
|
|
|
return NULL;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(__scsi_device_lookup);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* scsi_device_lookup - find a device given the host
|
|
|
|
* @shost: SCSI host pointer
|
|
|
|
* @channel: SCSI channel (zero if only one channel)
|
|
|
|
* @id: SCSI target number (physical unit number)
|
|
|
|
* @lun: SCSI Logical Unit Number
|
|
|
|
*
|
|
|
|
* Looks up the scsi_device with the specified @channel, @id, @lun for a
|
|
|
|
* give host. The returned scsi_device has an additional reference that
|
|
|
|
* needs to be release with scsi_host_put once you're done with it.
|
|
|
|
**/
|
|
|
|
struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost,
|
|
|
|
uint channel, uint id, uint lun)
|
|
|
|
{
|
|
|
|
struct scsi_device *sdev;
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
spin_lock_irqsave(shost->host_lock, flags);
|
|
|
|
sdev = __scsi_device_lookup(shost, channel, id, lun);
|
|
|
|
if (sdev && scsi_device_get(sdev))
|
|
|
|
sdev = NULL;
|
|
|
|
spin_unlock_irqrestore(shost->host_lock, flags);
|
|
|
|
|
|
|
|
return sdev;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(scsi_device_lookup);
|
|
|
|
|
|
|
|
/**
|
|
|
|
* scsi_device_cancel - cancel outstanding IO to this device
|
|
|
|
* @sdev: Pointer to struct scsi_device
|
|
|
|
* @recovery: Boolean instructing function to recover device or not.
|
|
|
|
*
|
|
|
|
**/
|
|
|
|
int scsi_device_cancel(struct scsi_device *sdev, int recovery)
|
|
|
|
{
|
|
|
|
struct scsi_cmnd *scmd;
|
|
|
|
LIST_HEAD(active_list);
|
|
|
|
struct list_head *lh, *lh_sf;
|
|
|
|
unsigned long flags;
|
|
|
|
|
|
|
|
scsi_device_set_state(sdev, SDEV_CANCEL);
|
|
|
|
|
|
|
|
spin_lock_irqsave(&sdev->list_lock, flags);
|
|
|
|
list_for_each_entry(scmd, &sdev->cmd_list, list) {
|
|
|
|
if (scmd->request && scmd->request->rq_status != RQ_INACTIVE) {
|
|
|
|
/*
|
|
|
|
* If we are unable to remove the timer, it means
|
|
|
|
* that the command has already timed out or
|
|
|
|
* finished.
|
|
|
|
*/
|
|
|
|
if (!scsi_delete_timer(scmd))
|
|
|
|
continue;
|
|
|
|
list_add_tail(&scmd->eh_entry, &active_list);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
spin_unlock_irqrestore(&sdev->list_lock, flags);
|
|
|
|
|
|
|
|
if (!list_empty(&active_list)) {
|
|
|
|
list_for_each_safe(lh, lh_sf, &active_list) {
|
|
|
|
scmd = list_entry(lh, struct scsi_cmnd, eh_entry);
|
|
|
|
list_del_init(lh);
|
|
|
|
if (recovery) {
|
|
|
|
scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD);
|
|
|
|
} else {
|
|
|
|
scmd->result = (DID_ABORT << 16);
|
|
|
|
scsi_finish_command(scmd);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(scsi_device_cancel);
|
|
|
|
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
|
|
static int scsi_cpu_notify(struct notifier_block *self,
|
|
|
|
unsigned long action, void *hcpu)
|
|
|
|
{
|
|
|
|
int cpu = (unsigned long)hcpu;
|
|
|
|
|
|
|
|
switch(action) {
|
|
|
|
case CPU_DEAD:
|
|
|
|
/* Drain scsi_done_q. */
|
|
|
|
local_irq_disable();
|
|
|
|
list_splice_init(&per_cpu(scsi_done_q, cpu),
|
|
|
|
&__get_cpu_var(scsi_done_q));
|
|
|
|
raise_softirq_irqoff(SCSI_SOFTIRQ);
|
|
|
|
local_irq_enable();
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
return NOTIFY_OK;
|
|
|
|
}
|
|
|
|
|
|
|
|
static struct notifier_block __devinitdata scsi_cpu_nb = {
|
|
|
|
.notifier_call = scsi_cpu_notify,
|
|
|
|
};
|
|
|
|
|
|
|
|
#define register_scsi_cpu() register_cpu_notifier(&scsi_cpu_nb)
|
|
|
|
#define unregister_scsi_cpu() unregister_cpu_notifier(&scsi_cpu_nb)
|
|
|
|
#else
|
|
|
|
#define register_scsi_cpu()
|
|
|
|
#define unregister_scsi_cpu()
|
|
|
|
#endif /* CONFIG_HOTPLUG_CPU */
|
|
|
|
|
|
|
|
MODULE_DESCRIPTION("SCSI core");
|
|
|
|
MODULE_LICENSE("GPL");
|
|
|
|
|
|
|
|
module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR);
|
|
|
|
MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels");
|
|
|
|
|
|
|
|
static int __init init_scsi(void)
|
|
|
|
{
|
|
|
|
int error, i;
|
|
|
|
|
|
|
|
error = scsi_init_queue();
|
|
|
|
if (error)
|
|
|
|
return error;
|
|
|
|
error = scsi_init_procfs();
|
|
|
|
if (error)
|
|
|
|
goto cleanup_queue;
|
|
|
|
error = scsi_init_devinfo();
|
|
|
|
if (error)
|
|
|
|
goto cleanup_procfs;
|
|
|
|
error = scsi_init_hosts();
|
|
|
|
if (error)
|
|
|
|
goto cleanup_devlist;
|
|
|
|
error = scsi_init_sysctl();
|
|
|
|
if (error)
|
|
|
|
goto cleanup_hosts;
|
|
|
|
error = scsi_sysfs_register();
|
|
|
|
if (error)
|
|
|
|
goto cleanup_sysctl;
|
|
|
|
|
|
|
|
for (i = 0; i < NR_CPUS; i++)
|
|
|
|
INIT_LIST_HEAD(&per_cpu(scsi_done_q, i));
|
|
|
|
|
|
|
|
devfs_mk_dir("scsi");
|
|
|
|
open_softirq(SCSI_SOFTIRQ, scsi_softirq, NULL);
|
|
|
|
register_scsi_cpu();
|
|
|
|
printk(KERN_NOTICE "SCSI subsystem initialized\n");
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
cleanup_sysctl:
|
|
|
|
scsi_exit_sysctl();
|
|
|
|
cleanup_hosts:
|
|
|
|
scsi_exit_hosts();
|
|
|
|
cleanup_devlist:
|
|
|
|
scsi_exit_devinfo();
|
|
|
|
cleanup_procfs:
|
|
|
|
scsi_exit_procfs();
|
|
|
|
cleanup_queue:
|
|
|
|
scsi_exit_queue();
|
|
|
|
printk(KERN_ERR "SCSI subsystem failed to initialize, error = %d\n",
|
|
|
|
-error);
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void __exit exit_scsi(void)
|
|
|
|
{
|
|
|
|
scsi_sysfs_unregister();
|
|
|
|
scsi_exit_sysctl();
|
|
|
|
scsi_exit_hosts();
|
|
|
|
scsi_exit_devinfo();
|
|
|
|
devfs_remove("scsi");
|
|
|
|
scsi_exit_procfs();
|
|
|
|
scsi_exit_queue();
|
|
|
|
unregister_scsi_cpu();
|
|
|
|
}
|
|
|
|
|
|
|
|
subsys_initcall(init_scsi);
|
|
|
|
module_exit(exit_scsi);
|