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f4ff08fab6
commitf23a4d6e07
upstream. Commitfc663711b9
("scsi: core: Remove the /proc/scsi/${proc_name} directory earlier") fixed a bug related to modules loading/unloading, by adding a call to scsi_proc_hostdir_rm() on scsi_remove_host(). But that led to a potential duplicate call to the hostdir_rm() routine, since it's also called from scsi_host_dev_release(). That triggered a regression report, which was then fixed by commitbe03df3d4b
("scsi: core: Fix a procfs host directory removal regression"). The fix just dropped the hostdir_rm() call from dev_release(). But it happens that this proc directory is created on scsi_host_alloc(), and that function "pairs" with scsi_host_dev_release(), while scsi_remove_host() pairs with scsi_add_host(). In other words, it seems the reason for removing the proc directory on dev_release() was meant to cover cases in which a SCSI host structure was allocated, but the call to scsi_add_host() didn't happen. And that pattern happens to exist in some error paths, for example. Syzkaller causes that by using USB raw gadget device, error'ing on usb-storage driver, at usb_stor_probe2(). By checking that path, we can see that the BadDevice label leads to a scsi_host_put() after a SCSI host allocation, but there's no call to scsi_add_host() in such path. That leads to messages like this in dmesg (and a leak of the SCSI host proc structure): usb-storage 4-1:87.51: USB Mass Storage device detected proc_dir_entry 'scsi/usb-storage' already registered WARNING: CPU: 1 PID: 3519 at fs/proc/generic.c:377 proc_register+0x347/0x4e0 fs/proc/generic.c:376 The proper fix seems to still call scsi_proc_hostdir_rm() on dev_release(), but guard that with the state check for SHOST_CREATED; there is even a comment in scsi_host_dev_release() detailing that: such conditional is meant for cases where the SCSI host was allocated but there was no calls to {add,remove}_host(), like the usb-storage case. This is what we propose here and with that, the error path of usb-storage does not trigger the warning anymore. Reported-by: syzbot+c645abf505ed21f931b5@syzkaller.appspotmail.com Fixes:be03df3d4b
("scsi: core: Fix a procfs host directory removal regression") Cc: stable@vger.kernel.org Cc: Bart Van Assche <bvanassche@acm.org> Cc: John Garry <john.g.garry@oracle.com> Cc: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com> Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com> Link: https://lore.kernel.org/r/20240313113006.2834799-1-gpiccoli@igalia.com Reviewed-by: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
746 lines
19 KiB
C
746 lines
19 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* hosts.c Copyright (C) 1992 Drew Eckhardt
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* Copyright (C) 1993, 1994, 1995 Eric Youngdale
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* Copyright (C) 2002-2003 Christoph Hellwig
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*
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* mid to lowlevel SCSI driver interface
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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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* Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli
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* Added QLOGIC QLA1280 SCSI controller kernel host support.
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* August 4, 1999 Fred Lewis, Intel DuPont
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*
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* Updated to reflect the new initialization scheme for the higher
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* level of scsi drivers (sd/sr/st)
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* September 17, 2000 Torben Mathiasen <tmm@image.dk>
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*
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* Restructured scsi_host lists and associated functions.
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* September 04, 2002 Mike Anderson (andmike@us.ibm.com)
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*/
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#include <linux/module.h>
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#include <linux/blkdev.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/kthread.h>
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#include <linux/string.h>
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#include <linux/mm.h>
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#include <linux/init.h>
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#include <linux/completion.h>
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#include <linux/transport_class.h>
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#include <linux/platform_device.h>
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#include <linux/pm_runtime.h>
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#include <linux/idr.h>
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#include <scsi/scsi_device.h>
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#include <scsi/scsi_host.h>
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#include <scsi/scsi_transport.h>
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#include <scsi/scsi_cmnd.h>
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#include "scsi_priv.h"
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#include "scsi_logging.h"
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static int shost_eh_deadline = -1;
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module_param_named(eh_deadline, shost_eh_deadline, int, S_IRUGO|S_IWUSR);
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MODULE_PARM_DESC(eh_deadline,
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"SCSI EH timeout in seconds (should be between 0 and 2^31-1)");
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static DEFINE_IDA(host_index_ida);
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static void scsi_host_cls_release(struct device *dev)
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{
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put_device(&class_to_shost(dev)->shost_gendev);
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}
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static struct class shost_class = {
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.name = "scsi_host",
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.dev_release = scsi_host_cls_release,
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.dev_groups = scsi_shost_groups,
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};
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/**
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* scsi_host_set_state - Take the given host through the host state model.
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* @shost: scsi host to change the state of.
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* @state: state to change to.
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*
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* Returns zero if unsuccessful or an error if the requested
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* transition is illegal.
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**/
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int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
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{
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enum scsi_host_state oldstate = shost->shost_state;
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if (state == oldstate)
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return 0;
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switch (state) {
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case SHOST_CREATED:
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/* There are no legal states that come back to
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* created. This is the manually initialised start
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* state */
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goto illegal;
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case SHOST_RUNNING:
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switch (oldstate) {
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case SHOST_CREATED:
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case SHOST_RECOVERY:
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break;
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default:
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goto illegal;
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}
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break;
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case SHOST_RECOVERY:
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switch (oldstate) {
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case SHOST_RUNNING:
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break;
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default:
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goto illegal;
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}
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break;
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case SHOST_CANCEL:
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switch (oldstate) {
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case SHOST_CREATED:
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case SHOST_RUNNING:
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case SHOST_CANCEL_RECOVERY:
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break;
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default:
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goto illegal;
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}
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break;
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case SHOST_DEL:
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switch (oldstate) {
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case SHOST_CANCEL:
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case SHOST_DEL_RECOVERY:
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break;
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default:
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goto illegal;
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}
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break;
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case SHOST_CANCEL_RECOVERY:
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switch (oldstate) {
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case SHOST_CANCEL:
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case SHOST_RECOVERY:
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break;
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default:
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goto illegal;
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}
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break;
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case SHOST_DEL_RECOVERY:
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switch (oldstate) {
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case SHOST_CANCEL_RECOVERY:
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break;
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default:
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goto illegal;
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}
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break;
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}
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shost->shost_state = state;
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return 0;
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illegal:
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SCSI_LOG_ERROR_RECOVERY(1,
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shost_printk(KERN_ERR, shost,
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"Illegal host state transition"
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"%s->%s\n",
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scsi_host_state_name(oldstate),
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scsi_host_state_name(state)));
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return -EINVAL;
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}
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/**
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* scsi_remove_host - remove a scsi host
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* @shost: a pointer to a scsi host to remove
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**/
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void scsi_remove_host(struct Scsi_Host *shost)
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{
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unsigned long flags;
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mutex_lock(&shost->scan_mutex);
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spin_lock_irqsave(shost->host_lock, flags);
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if (scsi_host_set_state(shost, SHOST_CANCEL))
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if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) {
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spin_unlock_irqrestore(shost->host_lock, flags);
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mutex_unlock(&shost->scan_mutex);
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return;
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}
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spin_unlock_irqrestore(shost->host_lock, flags);
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scsi_autopm_get_host(shost);
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flush_workqueue(shost->tmf_work_q);
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scsi_forget_host(shost);
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mutex_unlock(&shost->scan_mutex);
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scsi_proc_host_rm(shost);
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scsi_proc_hostdir_rm(shost->hostt);
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/*
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* New SCSI devices cannot be attached anymore because of the SCSI host
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* state so drop the tag set refcnt. Wait until the tag set refcnt drops
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* to zero because .exit_cmd_priv implementations may need the host
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* pointer.
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*/
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kref_put(&shost->tagset_refcnt, scsi_mq_free_tags);
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wait_for_completion(&shost->tagset_freed);
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spin_lock_irqsave(shost->host_lock, flags);
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if (scsi_host_set_state(shost, SHOST_DEL))
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BUG_ON(scsi_host_set_state(shost, SHOST_DEL_RECOVERY));
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spin_unlock_irqrestore(shost->host_lock, flags);
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transport_unregister_device(&shost->shost_gendev);
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device_unregister(&shost->shost_dev);
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device_del(&shost->shost_gendev);
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}
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EXPORT_SYMBOL(scsi_remove_host);
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/**
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* scsi_add_host_with_dma - add a scsi host with dma device
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* @shost: scsi host pointer to add
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* @dev: a struct device of type scsi class
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* @dma_dev: dma device for the host
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*
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* Note: You rarely need to worry about this unless you're in a
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* virtualised host environments, so use the simpler scsi_add_host()
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* function instead.
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*
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* Return value:
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* 0 on success / != 0 for error
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**/
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int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
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struct device *dma_dev)
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{
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const struct scsi_host_template *sht = shost->hostt;
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int error = -EINVAL;
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shost_printk(KERN_INFO, shost, "%s\n",
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sht->info ? sht->info(shost) : sht->name);
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if (!shost->can_queue) {
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shost_printk(KERN_ERR, shost,
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"can_queue = 0 no longer supported\n");
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goto fail;
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}
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/* Use min_t(int, ...) in case shost->can_queue exceeds SHRT_MAX */
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shost->cmd_per_lun = min_t(int, shost->cmd_per_lun,
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shost->can_queue);
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error = scsi_init_sense_cache(shost);
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if (error)
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goto fail;
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if (!shost->shost_gendev.parent)
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shost->shost_gendev.parent = dev ? dev : &platform_bus;
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if (!dma_dev)
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dma_dev = shost->shost_gendev.parent;
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shost->dma_dev = dma_dev;
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if (dma_dev->dma_mask) {
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shost->max_sectors = min_t(unsigned int, shost->max_sectors,
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dma_max_mapping_size(dma_dev) >> SECTOR_SHIFT);
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}
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error = scsi_mq_setup_tags(shost);
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if (error)
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goto fail;
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kref_init(&shost->tagset_refcnt);
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init_completion(&shost->tagset_freed);
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/*
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* Increase usage count temporarily here so that calling
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* scsi_autopm_put_host() will trigger runtime idle if there is
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* nothing else preventing suspending the device.
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*/
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pm_runtime_get_noresume(&shost->shost_gendev);
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pm_runtime_set_active(&shost->shost_gendev);
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pm_runtime_enable(&shost->shost_gendev);
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device_enable_async_suspend(&shost->shost_gendev);
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error = device_add(&shost->shost_gendev);
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if (error)
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goto out_disable_runtime_pm;
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scsi_host_set_state(shost, SHOST_RUNNING);
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get_device(shost->shost_gendev.parent);
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device_enable_async_suspend(&shost->shost_dev);
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get_device(&shost->shost_gendev);
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error = device_add(&shost->shost_dev);
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if (error)
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goto out_del_gendev;
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if (shost->transportt->host_size) {
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shost->shost_data = kzalloc(shost->transportt->host_size,
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GFP_KERNEL);
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if (shost->shost_data == NULL) {
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error = -ENOMEM;
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goto out_del_dev;
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}
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}
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if (shost->transportt->create_work_queue) {
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snprintf(shost->work_q_name, sizeof(shost->work_q_name),
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"scsi_wq_%d", shost->host_no);
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shost->work_q = alloc_workqueue("%s",
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WQ_SYSFS | __WQ_LEGACY | WQ_MEM_RECLAIM | WQ_UNBOUND,
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1, shost->work_q_name);
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if (!shost->work_q) {
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error = -EINVAL;
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goto out_del_dev;
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}
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}
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error = scsi_sysfs_add_host(shost);
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if (error)
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goto out_del_dev;
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scsi_proc_host_add(shost);
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scsi_autopm_put_host(shost);
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return error;
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/*
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* Any host allocation in this function will be freed in
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* scsi_host_dev_release().
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*/
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out_del_dev:
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device_del(&shost->shost_dev);
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out_del_gendev:
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/*
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* Host state is SHOST_RUNNING so we have to explicitly release
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* ->shost_dev.
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*/
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put_device(&shost->shost_dev);
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device_del(&shost->shost_gendev);
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out_disable_runtime_pm:
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device_disable_async_suspend(&shost->shost_gendev);
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pm_runtime_disable(&shost->shost_gendev);
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pm_runtime_set_suspended(&shost->shost_gendev);
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pm_runtime_put_noidle(&shost->shost_gendev);
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kref_put(&shost->tagset_refcnt, scsi_mq_free_tags);
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fail:
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return error;
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}
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EXPORT_SYMBOL(scsi_add_host_with_dma);
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static void scsi_host_dev_release(struct device *dev)
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{
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struct Scsi_Host *shost = dev_to_shost(dev);
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struct device *parent = dev->parent;
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/* Wait for functions invoked through call_rcu(&scmd->rcu, ...) */
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rcu_barrier();
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if (shost->tmf_work_q)
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destroy_workqueue(shost->tmf_work_q);
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if (shost->ehandler)
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kthread_stop(shost->ehandler);
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if (shost->work_q)
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destroy_workqueue(shost->work_q);
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if (shost->shost_state == SHOST_CREATED) {
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/*
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* Free the shost_dev device name and remove the proc host dir
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* here if scsi_host_{alloc,put}() have been called but neither
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* scsi_host_add() nor scsi_remove_host() has been called.
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* This avoids that the memory allocated for the shost_dev
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* name as well as the proc dir structure are leaked.
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*/
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scsi_proc_hostdir_rm(shost->hostt);
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kfree(dev_name(&shost->shost_dev));
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}
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kfree(shost->shost_data);
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ida_free(&host_index_ida, shost->host_no);
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if (shost->shost_state != SHOST_CREATED)
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put_device(parent);
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kfree(shost);
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}
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static struct device_type scsi_host_type = {
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.name = "scsi_host",
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.release = scsi_host_dev_release,
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};
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|
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/**
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* scsi_host_alloc - register a scsi host adapter instance.
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* @sht: pointer to scsi host template
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* @privsize: extra bytes to allocate for driver
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*
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* Note:
|
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* Allocate a new Scsi_Host and perform basic initialization.
|
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* The host is not published to the scsi midlayer until scsi_add_host
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* is called.
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*
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* Return value:
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* Pointer to a new Scsi_Host
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**/
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struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *sht, int privsize)
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{
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struct Scsi_Host *shost;
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int index;
|
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shost = kzalloc(sizeof(struct Scsi_Host) + privsize, GFP_KERNEL);
|
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if (!shost)
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return NULL;
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|
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shost->host_lock = &shost->default_lock;
|
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spin_lock_init(shost->host_lock);
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shost->shost_state = SHOST_CREATED;
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INIT_LIST_HEAD(&shost->__devices);
|
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INIT_LIST_HEAD(&shost->__targets);
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INIT_LIST_HEAD(&shost->eh_abort_list);
|
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INIT_LIST_HEAD(&shost->eh_cmd_q);
|
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INIT_LIST_HEAD(&shost->starved_list);
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init_waitqueue_head(&shost->host_wait);
|
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mutex_init(&shost->scan_mutex);
|
|
|
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index = ida_alloc(&host_index_ida, GFP_KERNEL);
|
|
if (index < 0) {
|
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kfree(shost);
|
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return NULL;
|
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}
|
|
shost->host_no = index;
|
|
|
|
shost->dma_channel = 0xff;
|
|
|
|
/* These three are default values which can be overridden */
|
|
shost->max_channel = 0;
|
|
shost->max_id = 8;
|
|
shost->max_lun = 8;
|
|
|
|
/* Give each shost a default transportt */
|
|
shost->transportt = &blank_transport_template;
|
|
|
|
/*
|
|
* All drivers right now should be able to handle 12 byte
|
|
* commands. Every so often there are requests for 16 byte
|
|
* commands, but individual low-level drivers need to certify that
|
|
* they actually do something sensible with such commands.
|
|
*/
|
|
shost->max_cmd_len = 12;
|
|
shost->hostt = sht;
|
|
shost->this_id = sht->this_id;
|
|
shost->can_queue = sht->can_queue;
|
|
shost->sg_tablesize = sht->sg_tablesize;
|
|
shost->sg_prot_tablesize = sht->sg_prot_tablesize;
|
|
shost->cmd_per_lun = sht->cmd_per_lun;
|
|
shost->no_write_same = sht->no_write_same;
|
|
shost->host_tagset = sht->host_tagset;
|
|
shost->queuecommand_may_block = sht->queuecommand_may_block;
|
|
|
|
if (shost_eh_deadline == -1 || !sht->eh_host_reset_handler)
|
|
shost->eh_deadline = -1;
|
|
else if ((ulong) shost_eh_deadline * HZ > INT_MAX) {
|
|
shost_printk(KERN_WARNING, shost,
|
|
"eh_deadline %u too large, setting to %u\n",
|
|
shost_eh_deadline, INT_MAX / HZ);
|
|
shost->eh_deadline = INT_MAX;
|
|
} else
|
|
shost->eh_deadline = shost_eh_deadline * HZ;
|
|
|
|
if (sht->supported_mode == MODE_UNKNOWN)
|
|
/* means we didn't set it ... default to INITIATOR */
|
|
shost->active_mode = MODE_INITIATOR;
|
|
else
|
|
shost->active_mode = sht->supported_mode;
|
|
|
|
if (sht->max_host_blocked)
|
|
shost->max_host_blocked = sht->max_host_blocked;
|
|
else
|
|
shost->max_host_blocked = SCSI_DEFAULT_HOST_BLOCKED;
|
|
|
|
/*
|
|
* If the driver imposes no hard sector transfer limit, start at
|
|
* machine infinity initially.
|
|
*/
|
|
if (sht->max_sectors)
|
|
shost->max_sectors = sht->max_sectors;
|
|
else
|
|
shost->max_sectors = SCSI_DEFAULT_MAX_SECTORS;
|
|
|
|
if (sht->max_segment_size)
|
|
shost->max_segment_size = sht->max_segment_size;
|
|
else
|
|
shost->max_segment_size = BLK_MAX_SEGMENT_SIZE;
|
|
|
|
/*
|
|
* assume a 4GB boundary, if not set
|
|
*/
|
|
if (sht->dma_boundary)
|
|
shost->dma_boundary = sht->dma_boundary;
|
|
else
|
|
shost->dma_boundary = 0xffffffff;
|
|
|
|
if (sht->virt_boundary_mask)
|
|
shost->virt_boundary_mask = sht->virt_boundary_mask;
|
|
|
|
device_initialize(&shost->shost_gendev);
|
|
dev_set_name(&shost->shost_gendev, "host%d", shost->host_no);
|
|
shost->shost_gendev.bus = &scsi_bus_type;
|
|
shost->shost_gendev.type = &scsi_host_type;
|
|
scsi_enable_async_suspend(&shost->shost_gendev);
|
|
|
|
device_initialize(&shost->shost_dev);
|
|
shost->shost_dev.parent = &shost->shost_gendev;
|
|
shost->shost_dev.class = &shost_class;
|
|
dev_set_name(&shost->shost_dev, "host%d", shost->host_no);
|
|
shost->shost_dev.groups = sht->shost_groups;
|
|
|
|
shost->ehandler = kthread_run(scsi_error_handler, shost,
|
|
"scsi_eh_%d", shost->host_no);
|
|
if (IS_ERR(shost->ehandler)) {
|
|
shost_printk(KERN_WARNING, shost,
|
|
"error handler thread failed to spawn, error = %ld\n",
|
|
PTR_ERR(shost->ehandler));
|
|
shost->ehandler = NULL;
|
|
goto fail;
|
|
}
|
|
|
|
shost->tmf_work_q = alloc_workqueue("scsi_tmf_%d",
|
|
WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS,
|
|
1, shost->host_no);
|
|
if (!shost->tmf_work_q) {
|
|
shost_printk(KERN_WARNING, shost,
|
|
"failed to create tmf workq\n");
|
|
goto fail;
|
|
}
|
|
if (scsi_proc_hostdir_add(shost->hostt) < 0)
|
|
goto fail;
|
|
return shost;
|
|
fail:
|
|
/*
|
|
* Host state is still SHOST_CREATED and that is enough to release
|
|
* ->shost_gendev. scsi_host_dev_release() will free
|
|
* dev_name(&shost->shost_dev).
|
|
*/
|
|
put_device(&shost->shost_gendev);
|
|
|
|
return NULL;
|
|
}
|
|
EXPORT_SYMBOL(scsi_host_alloc);
|
|
|
|
static int __scsi_host_match(struct device *dev, const void *data)
|
|
{
|
|
struct Scsi_Host *p;
|
|
const unsigned int *hostnum = data;
|
|
|
|
p = class_to_shost(dev);
|
|
return p->host_no == *hostnum;
|
|
}
|
|
|
|
/**
|
|
* scsi_host_lookup - get a reference to a Scsi_Host by host no
|
|
* @hostnum: host number to locate
|
|
*
|
|
* Return value:
|
|
* A pointer to located Scsi_Host or NULL.
|
|
*
|
|
* The caller must do a scsi_host_put() to drop the reference
|
|
* that scsi_host_get() took. The put_device() below dropped
|
|
* the reference from class_find_device().
|
|
**/
|
|
struct Scsi_Host *scsi_host_lookup(unsigned int hostnum)
|
|
{
|
|
struct device *cdev;
|
|
struct Scsi_Host *shost = NULL;
|
|
|
|
cdev = class_find_device(&shost_class, NULL, &hostnum,
|
|
__scsi_host_match);
|
|
if (cdev) {
|
|
shost = scsi_host_get(class_to_shost(cdev));
|
|
put_device(cdev);
|
|
}
|
|
return shost;
|
|
}
|
|
EXPORT_SYMBOL(scsi_host_lookup);
|
|
|
|
/**
|
|
* scsi_host_get - inc a Scsi_Host ref count
|
|
* @shost: Pointer to Scsi_Host to inc.
|
|
**/
|
|
struct Scsi_Host *scsi_host_get(struct Scsi_Host *shost)
|
|
{
|
|
if ((shost->shost_state == SHOST_DEL) ||
|
|
!get_device(&shost->shost_gendev))
|
|
return NULL;
|
|
return shost;
|
|
}
|
|
EXPORT_SYMBOL(scsi_host_get);
|
|
|
|
static bool scsi_host_check_in_flight(struct request *rq, void *data)
|
|
{
|
|
int *count = data;
|
|
struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq);
|
|
|
|
if (test_bit(SCMD_STATE_INFLIGHT, &cmd->state))
|
|
(*count)++;
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* scsi_host_busy - Return the host busy counter
|
|
* @shost: Pointer to Scsi_Host to inc.
|
|
**/
|
|
int scsi_host_busy(struct Scsi_Host *shost)
|
|
{
|
|
int cnt = 0;
|
|
|
|
blk_mq_tagset_busy_iter(&shost->tag_set,
|
|
scsi_host_check_in_flight, &cnt);
|
|
return cnt;
|
|
}
|
|
EXPORT_SYMBOL(scsi_host_busy);
|
|
|
|
/**
|
|
* scsi_host_put - dec a Scsi_Host ref count
|
|
* @shost: Pointer to Scsi_Host to dec.
|
|
**/
|
|
void scsi_host_put(struct Scsi_Host *shost)
|
|
{
|
|
put_device(&shost->shost_gendev);
|
|
}
|
|
EXPORT_SYMBOL(scsi_host_put);
|
|
|
|
int scsi_init_hosts(void)
|
|
{
|
|
return class_register(&shost_class);
|
|
}
|
|
|
|
void scsi_exit_hosts(void)
|
|
{
|
|
class_unregister(&shost_class);
|
|
ida_destroy(&host_index_ida);
|
|
}
|
|
|
|
int scsi_is_host_device(const struct device *dev)
|
|
{
|
|
return dev->type == &scsi_host_type;
|
|
}
|
|
EXPORT_SYMBOL(scsi_is_host_device);
|
|
|
|
/**
|
|
* scsi_queue_work - Queue work to the Scsi_Host workqueue.
|
|
* @shost: Pointer to Scsi_Host.
|
|
* @work: Work to queue for execution.
|
|
*
|
|
* Return value:
|
|
* 1 - work queued for execution
|
|
* 0 - work is already queued
|
|
* -EINVAL - work queue doesn't exist
|
|
**/
|
|
int scsi_queue_work(struct Scsi_Host *shost, struct work_struct *work)
|
|
{
|
|
if (unlikely(!shost->work_q)) {
|
|
shost_printk(KERN_ERR, shost,
|
|
"ERROR: Scsi host '%s' attempted to queue scsi-work, "
|
|
"when no workqueue created.\n", shost->hostt->name);
|
|
dump_stack();
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
return queue_work(shost->work_q, work);
|
|
}
|
|
EXPORT_SYMBOL_GPL(scsi_queue_work);
|
|
|
|
/**
|
|
* scsi_flush_work - Flush a Scsi_Host's workqueue.
|
|
* @shost: Pointer to Scsi_Host.
|
|
**/
|
|
void scsi_flush_work(struct Scsi_Host *shost)
|
|
{
|
|
if (!shost->work_q) {
|
|
shost_printk(KERN_ERR, shost,
|
|
"ERROR: Scsi host '%s' attempted to flush scsi-work, "
|
|
"when no workqueue created.\n", shost->hostt->name);
|
|
dump_stack();
|
|
return;
|
|
}
|
|
|
|
flush_workqueue(shost->work_q);
|
|
}
|
|
EXPORT_SYMBOL_GPL(scsi_flush_work);
|
|
|
|
static bool complete_all_cmds_iter(struct request *rq, void *data)
|
|
{
|
|
struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq);
|
|
enum scsi_host_status status = *(enum scsi_host_status *)data;
|
|
|
|
scsi_dma_unmap(scmd);
|
|
scmd->result = 0;
|
|
set_host_byte(scmd, status);
|
|
scsi_done(scmd);
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* scsi_host_complete_all_commands - Terminate all running commands
|
|
* @shost: Scsi Host on which commands should be terminated
|
|
* @status: Status to be set for the terminated commands
|
|
*
|
|
* There is no protection against modification of the number
|
|
* of outstanding commands. It is the responsibility of the
|
|
* caller to ensure that concurrent I/O submission and/or
|
|
* completion is stopped when calling this function.
|
|
*/
|
|
void scsi_host_complete_all_commands(struct Scsi_Host *shost,
|
|
enum scsi_host_status status)
|
|
{
|
|
blk_mq_tagset_busy_iter(&shost->tag_set, complete_all_cmds_iter,
|
|
&status);
|
|
}
|
|
EXPORT_SYMBOL_GPL(scsi_host_complete_all_commands);
|
|
|
|
struct scsi_host_busy_iter_data {
|
|
bool (*fn)(struct scsi_cmnd *, void *);
|
|
void *priv;
|
|
};
|
|
|
|
static bool __scsi_host_busy_iter_fn(struct request *req, void *priv)
|
|
{
|
|
struct scsi_host_busy_iter_data *iter_data = priv;
|
|
struct scsi_cmnd *sc = blk_mq_rq_to_pdu(req);
|
|
|
|
return iter_data->fn(sc, iter_data->priv);
|
|
}
|
|
|
|
/**
|
|
* scsi_host_busy_iter - Iterate over all busy commands
|
|
* @shost: Pointer to Scsi_Host.
|
|
* @fn: Function to call on each busy command
|
|
* @priv: Data pointer passed to @fn
|
|
*
|
|
* If locking against concurrent command completions is required
|
|
* ithas to be provided by the caller
|
|
**/
|
|
void scsi_host_busy_iter(struct Scsi_Host *shost,
|
|
bool (*fn)(struct scsi_cmnd *, void *),
|
|
void *priv)
|
|
{
|
|
struct scsi_host_busy_iter_data iter_data = {
|
|
.fn = fn,
|
|
.priv = priv,
|
|
};
|
|
|
|
blk_mq_tagset_busy_iter(&shost->tag_set, __scsi_host_busy_iter_fn,
|
|
&iter_data);
|
|
}
|
|
EXPORT_SYMBOL_GPL(scsi_host_busy_iter);
|