![Vitaly Wool](/assets/img/avatar_default.png)
Currently on SD/MMC card removal the system exhibits the following message (the platform is ARM Versatile): prev->state: 2 != TASK_RUNNING?? mmcqd/762[CPU#0]: BUG in __schedule at linux-2.6/kernel/sched.c:3826 (akpm: someone tried to fix this, but it's still wrong) Signed-off-by: Vitaly Wool <vitalywool@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
251 lines
5.6 KiB
C
251 lines
5.6 KiB
C
/*
|
|
* linux/drivers/mmc/mmc_queue.c
|
|
*
|
|
* Copyright (C) 2003 Russell King, All Rights Reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
*/
|
|
#include <linux/module.h>
|
|
#include <linux/blkdev.h>
|
|
#include <linux/kthread.h>
|
|
|
|
#include <linux/mmc/card.h>
|
|
#include <linux/mmc/host.h>
|
|
#include "mmc_queue.h"
|
|
|
|
#define MMC_QUEUE_SUSPENDED (1 << 0)
|
|
|
|
/*
|
|
* Prepare a MMC request. Essentially, this means passing the
|
|
* preparation off to the media driver. The media driver will
|
|
* create a mmc_io_request in req->special.
|
|
*/
|
|
static int mmc_prep_request(struct request_queue *q, struct request *req)
|
|
{
|
|
struct mmc_queue *mq = q->queuedata;
|
|
int ret = BLKPREP_KILL;
|
|
|
|
if (blk_special_request(req)) {
|
|
/*
|
|
* Special commands already have the command
|
|
* blocks already setup in req->special.
|
|
*/
|
|
BUG_ON(!req->special);
|
|
|
|
ret = BLKPREP_OK;
|
|
} else if (blk_fs_request(req) || blk_pc_request(req)) {
|
|
/*
|
|
* Block I/O requests need translating according
|
|
* to the protocol.
|
|
*/
|
|
ret = mq->prep_fn(mq, req);
|
|
} else {
|
|
/*
|
|
* Everything else is invalid.
|
|
*/
|
|
blk_dump_rq_flags(req, "MMC bad request");
|
|
}
|
|
|
|
if (ret == BLKPREP_OK)
|
|
req->cmd_flags |= REQ_DONTPREP;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int mmc_queue_thread(void *d)
|
|
{
|
|
struct mmc_queue *mq = d;
|
|
struct request_queue *q = mq->queue;
|
|
|
|
/*
|
|
* Set iothread to ensure that we aren't put to sleep by
|
|
* the process freezing. We handle suspension ourselves.
|
|
*/
|
|
current->flags |= PF_MEMALLOC|PF_NOFREEZE;
|
|
|
|
down(&mq->thread_sem);
|
|
do {
|
|
struct request *req = NULL;
|
|
|
|
spin_lock_irq(q->queue_lock);
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
if (!blk_queue_plugged(q))
|
|
req = elv_next_request(q);
|
|
mq->req = req;
|
|
spin_unlock_irq(q->queue_lock);
|
|
|
|
if (!req) {
|
|
if (kthread_should_stop()) {
|
|
set_current_state(TASK_RUNNING);
|
|
break;
|
|
}
|
|
up(&mq->thread_sem);
|
|
schedule();
|
|
down(&mq->thread_sem);
|
|
continue;
|
|
}
|
|
set_current_state(TASK_RUNNING);
|
|
|
|
mq->issue_fn(mq, req);
|
|
} while (1);
|
|
up(&mq->thread_sem);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Generic MMC request handler. This is called for any queue on a
|
|
* particular host. When the host is not busy, we look for a request
|
|
* on any queue on this host, and attempt to issue it. This may
|
|
* not be the queue we were asked to process.
|
|
*/
|
|
static void mmc_request(request_queue_t *q)
|
|
{
|
|
struct mmc_queue *mq = q->queuedata;
|
|
struct request *req;
|
|
int ret;
|
|
|
|
if (!mq) {
|
|
printk(KERN_ERR "MMC: killing requests for dead queue\n");
|
|
while ((req = elv_next_request(q)) != NULL) {
|
|
do {
|
|
ret = end_that_request_chunk(req, 0,
|
|
req->current_nr_sectors << 9);
|
|
} while (ret);
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (!mq->req)
|
|
wake_up_process(mq->thread);
|
|
}
|
|
|
|
/**
|
|
* mmc_init_queue - initialise a queue structure.
|
|
* @mq: mmc queue
|
|
* @card: mmc card to attach this queue
|
|
* @lock: queue lock
|
|
*
|
|
* Initialise a MMC card request queue.
|
|
*/
|
|
int mmc_init_queue(struct mmc_queue *mq, struct mmc_card *card, spinlock_t *lock)
|
|
{
|
|
struct mmc_host *host = card->host;
|
|
u64 limit = BLK_BOUNCE_HIGH;
|
|
int ret;
|
|
|
|
if (mmc_dev(host)->dma_mask && *mmc_dev(host)->dma_mask)
|
|
limit = *mmc_dev(host)->dma_mask;
|
|
|
|
mq->card = card;
|
|
mq->queue = blk_init_queue(mmc_request, lock);
|
|
if (!mq->queue)
|
|
return -ENOMEM;
|
|
|
|
blk_queue_prep_rq(mq->queue, mmc_prep_request);
|
|
blk_queue_bounce_limit(mq->queue, limit);
|
|
blk_queue_max_sectors(mq->queue, host->max_sectors);
|
|
blk_queue_max_phys_segments(mq->queue, host->max_phys_segs);
|
|
blk_queue_max_hw_segments(mq->queue, host->max_hw_segs);
|
|
blk_queue_max_segment_size(mq->queue, host->max_seg_size);
|
|
|
|
mq->queue->queuedata = mq;
|
|
mq->req = NULL;
|
|
|
|
mq->sg = kmalloc(sizeof(struct scatterlist) * host->max_phys_segs,
|
|
GFP_KERNEL);
|
|
if (!mq->sg) {
|
|
ret = -ENOMEM;
|
|
goto cleanup_queue;
|
|
}
|
|
|
|
init_MUTEX(&mq->thread_sem);
|
|
|
|
mq->thread = kthread_run(mmc_queue_thread, mq, "mmcqd");
|
|
if (IS_ERR(mq->thread)) {
|
|
ret = PTR_ERR(mq->thread);
|
|
goto free_sg;
|
|
}
|
|
|
|
return 0;
|
|
|
|
free_sg:
|
|
kfree(mq->sg);
|
|
mq->sg = NULL;
|
|
cleanup_queue:
|
|
blk_cleanup_queue(mq->queue);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(mmc_init_queue);
|
|
|
|
void mmc_cleanup_queue(struct mmc_queue *mq)
|
|
{
|
|
request_queue_t *q = mq->queue;
|
|
unsigned long flags;
|
|
|
|
/* Mark that we should start throwing out stragglers */
|
|
spin_lock_irqsave(q->queue_lock, flags);
|
|
q->queuedata = NULL;
|
|
spin_unlock_irqrestore(q->queue_lock, flags);
|
|
|
|
/* Then terminate our worker thread */
|
|
kthread_stop(mq->thread);
|
|
|
|
kfree(mq->sg);
|
|
mq->sg = NULL;
|
|
|
|
blk_cleanup_queue(mq->queue);
|
|
|
|
mq->card = NULL;
|
|
}
|
|
EXPORT_SYMBOL(mmc_cleanup_queue);
|
|
|
|
/**
|
|
* mmc_queue_suspend - suspend a MMC request queue
|
|
* @mq: MMC queue to suspend
|
|
*
|
|
* Stop the block request queue, and wait for our thread to
|
|
* complete any outstanding requests. This ensures that we
|
|
* won't suspend while a request is being processed.
|
|
*/
|
|
void mmc_queue_suspend(struct mmc_queue *mq)
|
|
{
|
|
request_queue_t *q = mq->queue;
|
|
unsigned long flags;
|
|
|
|
if (!(mq->flags & MMC_QUEUE_SUSPENDED)) {
|
|
mq->flags |= MMC_QUEUE_SUSPENDED;
|
|
|
|
spin_lock_irqsave(q->queue_lock, flags);
|
|
blk_stop_queue(q);
|
|
spin_unlock_irqrestore(q->queue_lock, flags);
|
|
|
|
down(&mq->thread_sem);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(mmc_queue_suspend);
|
|
|
|
/**
|
|
* mmc_queue_resume - resume a previously suspended MMC request queue
|
|
* @mq: MMC queue to resume
|
|
*/
|
|
void mmc_queue_resume(struct mmc_queue *mq)
|
|
{
|
|
request_queue_t *q = mq->queue;
|
|
unsigned long flags;
|
|
|
|
if (mq->flags & MMC_QUEUE_SUSPENDED) {
|
|
mq->flags &= ~MMC_QUEUE_SUSPENDED;
|
|
|
|
up(&mq->thread_sem);
|
|
|
|
spin_lock_irqsave(q->queue_lock, flags);
|
|
blk_start_queue(q);
|
|
spin_unlock_irqrestore(q->queue_lock, flags);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(mmc_queue_resume);
|