Merge branch 'linux-2.6'

5 files changed, 977 insertions, 0 deletions

diff --git a/drivers/mmc/card/Kconfig b/drivers/mmc/card/Kconfig
new file mode 100644
index 0000000..01a9fd3
--- /dev/null
+++ b/drivers/mmc/card/Kconfig
@@ -0,0 +1,17 @@
+#
+# MMC/SD card drivers
+#
+
+comment "MMC/SD Card Drivers"
+	depends MMC
+
+config MMC_BLOCK
+	tristate "MMC block device driver"
+	depends on MMC && BLOCK
+	default y
+	help
+	  Say Y here to enable the MMC block device driver support.
+	  This provides a block device driver, which you can use to
+	  mount the filesystem. Almost everyone wishing MMC support
+	  should say Y or M here.
+
diff --git a/drivers/mmc/card/Makefile b/drivers/mmc/card/Makefile
new file mode 100644
index 0000000..cf8c939
--- /dev/null
+++ b/drivers/mmc/card/Makefile
@@ -0,0 +1,11 @@
+#
+# Makefile for MMC/SD card drivers
+#
+
+ifeq ($(CONFIG_MMC_DEBUG),y)
+	EXTRA_CFLAGS		+= -DDEBUG
+endif
+
+obj-$(CONFIG_MMC_BLOCK)		+= mmc_block.o
+mmc_block-objs			:= block.o queue.o
+
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
new file mode 100644
index 0000000..d24ab23
--- /dev/null
+++ b/drivers/mmc/card/block.c
@@ -0,0 +1,665 @@
+/*
+ * Block driver for media (i.e., flash cards)
+ *
+ * Copyright 2002 Hewlett-Packard Company
+ * Copyright 2005-2007 Pierre Ossman
+ *
+ * Use consistent with the GNU GPL is permitted,
+ * provided that this copyright notice is
+ * preserved in its entirety in all copies and derived works.
+ *
+ * HEWLETT-PACKARD COMPANY MAKES NO WARRANTIES, EXPRESSED OR IMPLIED,
+ * AS TO THE USEFULNESS OR CORRECTNESS OF THIS CODE OR ITS
+ * FITNESS FOR ANY PARTICULAR PURPOSE.
+ *
+ * Many thanks to Alessandro Rubini and Jonathan Corbet!
+ *
+ * Author:  Andrew Christian
+ *          28 May 2002
+ */
+#include <linux/moduleparam.h>
+#include <linux/module.h>
+#include <linux/init.h>
+
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/hdreg.h>
+#include <linux/kdev_t.h>
+#include <linux/blkdev.h>
+#include <linux/mutex.h>
+#include <linux/scatterlist.h>
+
+#include <linux/mmc/card.h>
+#include <linux/mmc/host.h>
+#include <linux/mmc/mmc.h>
+#include <linux/mmc/sd.h>
+
+#include <asm/system.h>
+#include <asm/uaccess.h>
+
+#include "queue.h"
+
+/*
+ * max 8 partitions per card
+ */
+#define MMC_SHIFT	3
+
+static int major;
+
+/*
+ * There is one mmc_blk_data per slot.
+ */
+struct mmc_blk_data {
+	spinlock_t	lock;
+	struct gendisk	*disk;
+	struct mmc_queue queue;
+
+	unsigned int	usage;
+	unsigned int	block_bits;
+	unsigned int	read_only;
+};
+
+static DEFINE_MUTEX(open_lock);
+
+static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
+{
+	struct mmc_blk_data *md;
+
+	mutex_lock(&open_lock);
+	md = disk->private_data;
+	if (md && md->usage == 0)
+		md = NULL;
+	if (md)
+		md->usage++;
+	mutex_unlock(&open_lock);
+
+	return md;
+}
+
+static void mmc_blk_put(struct mmc_blk_data *md)
+{
+	mutex_lock(&open_lock);
+	md->usage--;
+	if (md->usage == 0) {
+		put_disk(md->disk);
+		kfree(md);
+	}
+	mutex_unlock(&open_lock);
+}
+
+static int mmc_blk_open(struct inode *inode, struct file *filp)
+{
+	struct mmc_blk_data *md;
+	int ret = -ENXIO;
+
+	md = mmc_blk_get(inode->i_bdev->bd_disk);
+	if (md) {
+		if (md->usage == 2)
+			check_disk_change(inode->i_bdev);
+		ret = 0;
+
+		if ((filp->f_mode & FMODE_WRITE) && md->read_only)
+			ret = -EROFS;
+	}
+
+	return ret;
+}
+
+static int mmc_blk_release(struct inode *inode, struct file *filp)
+{
+	struct mmc_blk_data *md = inode->i_bdev->bd_disk->private_data;
+
+	mmc_blk_put(md);
+	return 0;
+}
+
+static int
+mmc_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
+{
+	geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
+	geo->heads = 4;
+	geo->sectors = 16;
+	return 0;
+}
+
+static struct block_device_operations mmc_bdops = {
+	.open			= mmc_blk_open,
+	.release		= mmc_blk_release,
+	.getgeo			= mmc_blk_getgeo,
+	.owner			= THIS_MODULE,
+};
+
+struct mmc_blk_request {
+	struct mmc_request	mrq;
+	struct mmc_command	cmd;
+	struct mmc_command	stop;
+	struct mmc_data		data;
+};
+
+static int mmc_blk_prep_rq(struct mmc_queue *mq, struct request *req)
+{
+	struct mmc_blk_data *md = mq->data;
+	int stat = BLKPREP_OK;
+
+	/*
+	 * If we have no device, we haven't finished initialising.
+	 */
+	if (!md || !mq->card) {
+		printk(KERN_ERR "%s: killing request - no device/host\n",
+		       req->rq_disk->disk_name);
+		stat = BLKPREP_KILL;
+	}
+
+	return stat;
+}
+
+static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
+{
+	int err;
+	u32 blocks;
+
+	struct mmc_request mrq;
+	struct mmc_command cmd;
+	struct mmc_data data;
+	unsigned int timeout_us;
+
+	struct scatterlist sg;
+
+	memset(&cmd, 0, sizeof(struct mmc_command));
+
+	cmd.opcode = MMC_APP_CMD;
+	cmd.arg = card->rca << 16;
+	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
+
+	err = mmc_wait_for_cmd(card->host, &cmd, 0);
+	if ((err != MMC_ERR_NONE) || !(cmd.resp[0] & R1_APP_CMD))
+		return (u32)-1;
+
+	memset(&cmd, 0, sizeof(struct mmc_command));
+
+	cmd.opcode = SD_APP_SEND_NUM_WR_BLKS;
+	cmd.arg = 0;
+	cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
+
+	memset(&data, 0, sizeof(struct mmc_data));
+
+	data.timeout_ns = card->csd.tacc_ns * 100;
+	data.timeout_clks = card->csd.tacc_clks * 100;
+
+	timeout_us = data.timeout_ns / 1000;
+	timeout_us += data.timeout_clks * 1000 /
+		(card->host->ios.clock / 1000);
+
+	if (timeout_us > 100000) {
+		data.timeout_ns = 100000000;
+		data.timeout_clks = 0;
+	}
+
+	data.blksz = 4;
+	data.blocks = 1;
+	data.flags = MMC_DATA_READ;
+	data.sg = &sg;
+	data.sg_len = 1;
+
+	memset(&mrq, 0, sizeof(struct mmc_request));
+
+	mrq.cmd = &cmd;
+	mrq.data = &data;
+
+	sg_init_one(&sg, &blocks, 4);
+
+	mmc_wait_for_req(card->host, &mrq);
+
+	if (cmd.error != MMC_ERR_NONE || data.error != MMC_ERR_NONE)
+		return (u32)-1;
+
+	blocks = ntohl(blocks);
+
+	return blocks;
+}
+
+static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
+{
+	struct mmc_blk_data *md = mq->data;
+	struct mmc_card *card = md->queue.card;
+	struct mmc_blk_request brq;
+	int ret = 1, sg_pos, data_size;
+
+	mmc_claim_host(card->host);
+
+	do {
+		struct mmc_command cmd;
+		u32 readcmd, writecmd;
+
+		memset(&brq, 0, sizeof(struct mmc_blk_request));
+		brq.mrq.cmd = &brq.cmd;
+		brq.mrq.data = &brq.data;
+
+		brq.cmd.arg = req->sector;
+		if (!mmc_card_blockaddr(card))
+			brq.cmd.arg <<= 9;
+		brq.cmd.flags = MMC_RSP_R1 | MMC_CMD_ADTC;
+		brq.data.blksz = 1 << md->block_bits;
+		brq.stop.opcode = MMC_STOP_TRANSMISSION;
+		brq.stop.arg = 0;
+		brq.stop.flags = MMC_RSP_R1B | MMC_CMD_AC;
+		brq.data.blocks = req->nr_sectors >> (md->block_bits - 9);
+		if (brq.data.blocks > card->host->max_blk_count)
+			brq.data.blocks = card->host->max_blk_count;
+
+		mmc_set_data_timeout(&brq.data, card, rq_data_dir(req) != READ);
+
+		/*
+		 * If the host doesn't support multiple block writes, force
+		 * block writes to single block. SD cards are excepted from
+		 * this rule as they support querying the number of
+		 * successfully written sectors.
+		 */
+		if (rq_data_dir(req) != READ &&
+		    !(card->host->caps & MMC_CAP_MULTIWRITE) &&
+		    !mmc_card_sd(card))
+			brq.data.blocks = 1;
+
+		if (brq.data.blocks > 1) {
+			brq.data.flags |= MMC_DATA_MULTI;
+			brq.mrq.stop = &brq.stop;
+			readcmd = MMC_READ_MULTIPLE_BLOCK;
+			writecmd = MMC_WRITE_MULTIPLE_BLOCK;
+		} else {
+			brq.mrq.stop = NULL;
+			readcmd = MMC_READ_SINGLE_BLOCK;
+			writecmd = MMC_WRITE_BLOCK;
+		}
+
+		if (rq_data_dir(req) == READ) {
+			brq.cmd.opcode = readcmd;
+			brq.data.flags |= MMC_DATA_READ;
+		} else {
+			brq.cmd.opcode = writecmd;
+			brq.data.flags |= MMC_DATA_WRITE;
+		}
+
+		brq.data.sg = mq->sg;
+		brq.data.sg_len = blk_rq_map_sg(req->q, req, brq.data.sg);
+
+		if (brq.data.blocks !=
+		    (req->nr_sectors >> (md->block_bits - 9))) {
+			data_size = brq.data.blocks * brq.data.blksz;
+			for (sg_pos = 0; sg_pos < brq.data.sg_len; sg_pos++) {
+				data_size -= mq->sg[sg_pos].length;
+				if (data_size <= 0) {
+					mq->sg[sg_pos].length += data_size;
+					sg_pos++;
+					break;
+				}
+			}
+			brq.data.sg_len = sg_pos;
+		}
+
+		mmc_wait_for_req(card->host, &brq.mrq);
+		if (brq.cmd.error) {
+			printk(KERN_ERR "%s: error %d sending read/write command\n",
+			       req->rq_disk->disk_name, brq.cmd.error);
+			goto cmd_err;
+		}
+
+		if (brq.data.error) {
+			printk(KERN_ERR "%s: error %d transferring data\n",
+			       req->rq_disk->disk_name, brq.data.error);
+			goto cmd_err;
+		}
+
+		if (brq.stop.error) {
+			printk(KERN_ERR "%s: error %d sending stop command\n",
+			       req->rq_disk->disk_name, brq.stop.error);
+			goto cmd_err;
+		}
+
+		if (rq_data_dir(req) != READ) {
+			do {
+				int err;
+
+				cmd.opcode = MMC_SEND_STATUS;
+				cmd.arg = card->rca << 16;
+				cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
+				err = mmc_wait_for_cmd(card->host, &cmd, 5);
+				if (err) {
+					printk(KERN_ERR "%s: error %d requesting status\n",
+					       req->rq_disk->disk_name, err);
+					goto cmd_err;
+				}
+			} while (!(cmd.resp[0] & R1_READY_FOR_DATA));
+
+#if 0
+			if (cmd.resp[0] & ~0x00000900)
+				printk(KERN_ERR "%s: status = %08x\n",
+				       req->rq_disk->disk_name, cmd.resp[0]);
+			if (mmc_decode_status(cmd.resp))
+				goto cmd_err;
+#endif
+		}
+
+		/*
+		 * A block was successfully transferred.
+		 */
+		spin_lock_irq(&md->lock);
+		ret = end_that_request_chunk(req, 1, brq.data.bytes_xfered);
+		if (!ret) {
+			/*
+			 * The whole request completed successfully.
+			 */
+			add_disk_randomness(req->rq_disk);
+			blkdev_dequeue_request(req);
+			end_that_request_last(req, 1);
+		}
+		spin_unlock_irq(&md->lock);
+	} while (ret);
+
+	mmc_release_host(card->host);
+
+	return 1;
+
+ cmd_err:
+ 	/*
+ 	 * If this is an SD card and we're writing, we can first
+ 	 * mark the known good sectors as ok.
+ 	 *
+	 * If the card is not SD, we can still ok written sectors
+	 * if the controller can do proper error reporting.
+	 *
+	 * For reads we just fail the entire chunk as that should
+	 * be safe in all cases.
+	 */
+ 	if (rq_data_dir(req) != READ && mmc_card_sd(card)) {
+		u32 blocks;
+		unsigned int bytes;
+
+		blocks = mmc_sd_num_wr_blocks(card);
+		if (blocks != (u32)-1) {
+			if (card->csd.write_partial)
+				bytes = blocks << md->block_bits;
+			else
+				bytes = blocks << 9;
+			spin_lock_irq(&md->lock);
+			ret = end_that_request_chunk(req, 1, bytes);
+			spin_unlock_irq(&md->lock);
+		}
+	} else if (rq_data_dir(req) != READ &&
+		   (card->host->caps & MMC_CAP_MULTIWRITE)) {
+		spin_lock_irq(&md->lock);
+		ret = end_that_request_chunk(req, 1, brq.data.bytes_xfered);
+		spin_unlock_irq(&md->lock);
+	}
+
+	mmc_release_host(card->host);
+
+	spin_lock_irq(&md->lock);
+	while (ret) {
+		ret = end_that_request_chunk(req, 0,
+				req->current_nr_sectors << 9);
+	}
+
+	add_disk_randomness(req->rq_disk);
+	blkdev_dequeue_request(req);
+	end_that_request_last(req, 0);
+	spin_unlock_irq(&md->lock);
+
+	return 0;
+}
+
+#define MMC_NUM_MINORS	(256 >> MMC_SHIFT)
+
+static unsigned long dev_use[MMC_NUM_MINORS/(8*sizeof(unsigned long))];
+
+static inline int mmc_blk_readonly(struct mmc_card *card)
+{
+	return mmc_card_readonly(card) ||
+	       !(card->csd.cmdclass & CCC_BLOCK_WRITE);
+}
+
+static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
+{
+	struct mmc_blk_data *md;
+	int devidx, ret;
+
+	devidx = find_first_zero_bit(dev_use, MMC_NUM_MINORS);
+	if (devidx >= MMC_NUM_MINORS)
+		return ERR_PTR(-ENOSPC);
+	__set_bit(devidx, dev_use);
+
+	md = kmalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
+	if (!md) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	memset(md, 0, sizeof(struct mmc_blk_data));
+
+	/*
+	 * Set the read-only status based on the supported commands
+	 * and the write protect switch.
+	 */
+	md->read_only = mmc_blk_readonly(card);
+
+	/*
+	 * Both SD and MMC specifications state (although a bit
+	 * unclearly in the MMC case) that a block size of 512
+	 * bytes must always be supported by the card.
+	 */
+	md->block_bits = 9;
+
+	md->disk = alloc_disk(1 << MMC_SHIFT);
+	if (md->disk == NULL) {
+		ret = -ENOMEM;
+		goto err_kfree;
+	}
+
+	spin_lock_init(&md->lock);
+	md->usage = 1;
+
+	ret = mmc_init_queue(&md->queue, card, &md->lock);
+	if (ret)
+		goto err_putdisk;
+
+	md->queue.prep_fn = mmc_blk_prep_rq;
+	md->queue.issue_fn = mmc_blk_issue_rq;
+	md->queue.data = md;
+
+	md->disk->major	= major;
+	md->disk->first_minor = devidx << MMC_SHIFT;
+	md->disk->fops = &mmc_bdops;
+	md->disk->private_data = md;
+	md->disk->queue = md->queue.queue;
+	md->disk->driverfs_dev = &card->dev;
+
+	/*
+	 * As discussed on lkml, GENHD_FL_REMOVABLE should:
+	 *
+	 * - be set for removable media with permanent block devices
+	 * - be unset for removable block devices with permanent media
+	 *
+	 * Since MMC block devices clearly fall under the second
+	 * case, we do not set GENHD_FL_REMOVABLE.  Userspace
+	 * should use the block device creation/destruction hotplug
+	 * messages to tell when the card is present.
+	 */
+
+	sprintf(md->disk->disk_name, "mmcblk%d", devidx);
+
+	blk_queue_hardsect_size(md->queue.queue, 1 << md->block_bits);
+
+	if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
+		/*
+		 * The EXT_CSD sector count is in number or 512 byte
+		 * sectors.
+		 */
+		set_capacity(md->disk, card->ext_csd.sectors);
+	} else {
+		/*
+		 * The CSD capacity field is in units of read_blkbits.
+		 * set_capacity takes units of 512 bytes.
+		 */
+		set_capacity(md->disk,
+			card->csd.capacity << (card->csd.read_blkbits - 9));
+	}
+	return md;
+
+ err_putdisk:
+	put_disk(md->disk);
+ err_kfree:
+	kfree(md);
+ out:
+	return ERR_PTR(ret);
+}
+
+static int
+mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
+{
+	struct mmc_command cmd;
+	int err;
+
+	/* Block-addressed cards ignore MMC_SET_BLOCKLEN. */
+	if (mmc_card_blockaddr(card))
+		return 0;
+
+	mmc_claim_host(card->host);
+	cmd.opcode = MMC_SET_BLOCKLEN;
+	cmd.arg = 1 << md->block_bits;
+	cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
+	err = mmc_wait_for_cmd(card->host, &cmd, 5);
+	mmc_release_host(card->host);
+
+	if (err) {
+		printk(KERN_ERR "%s: unable to set block size to %d: %d\n",
+			md->disk->disk_name, cmd.arg, err);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int mmc_blk_probe(struct mmc_card *card)
+{
+	struct mmc_blk_data *md;
+	int err;
+
+	/*
+	 * Check that the card supports the command class(es) we need.
+	 */
+	if (!(card->csd.cmdclass & CCC_BLOCK_READ))
+		return -ENODEV;
+
+	md = mmc_blk_alloc(card);
+	if (IS_ERR(md))
+		return PTR_ERR(md);
+
+	err = mmc_blk_set_blksize(md, card);
+	if (err)
+		goto out;
+
+	printk(KERN_INFO "%s: %s %s %lluKiB %s\n",
+		md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
+		(unsigned long long)(get_capacity(md->disk) >> 1),
+		md->read_only ? "(ro)" : "");
+
+	mmc_set_drvdata(card, md);
+	add_disk(md->disk);
+	return 0;
+
+ out:
+	mmc_blk_put(md);
+
+	return err;
+}
+
+static void mmc_blk_remove(struct mmc_card *card)
+{
+	struct mmc_blk_data *md = mmc_get_drvdata(card);
+
+	if (md) {
+		int devidx;
+
+		/* Stop new requests from getting into the queue */
+		del_gendisk(md->disk);
+
+		/* Then flush out any already in there */
+		mmc_cleanup_queue(&md->queue);
+
+		devidx = md->disk->first_minor >> MMC_SHIFT;
+		__clear_bit(devidx, dev_use);
+
+		mmc_blk_put(md);
+	}
+	mmc_set_drvdata(card, NULL);
+}
+
+#ifdef CONFIG_PM
+static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
+{
+	struct mmc_blk_data *md = mmc_get_drvdata(card);
+
+	if (md) {
+		mmc_queue_suspend(&md->queue);
+	}
+	return 0;
+}
+
+static int mmc_blk_resume(struct mmc_card *card)
+{
+	struct mmc_blk_data *md = mmc_get_drvdata(card);
+
+	if (md) {
+		mmc_blk_set_blksize(md, card);
+		mmc_queue_resume(&md->queue);
+	}
+	return 0;
+}
+#else
+#define	mmc_blk_suspend	NULL
+#define mmc_blk_resume	NULL
+#endif
+
+static struct mmc_driver mmc_driver = {
+	.drv		= {
+		.name	= "mmcblk",
+	},
+	.probe		= mmc_blk_probe,
+	.remove		= mmc_blk_remove,
+	.suspend	= mmc_blk_suspend,
+	.resume		= mmc_blk_resume,
+};
+
+static int __init mmc_blk_init(void)
+{
+	int res = -ENOMEM;
+
+	res = register_blkdev(major, "mmc");
+	if (res < 0) {
+		printk(KERN_WARNING "Unable to get major %d for MMC media: %d\n",
+		       major, res);
+		goto out;
+	}
+	if (major == 0)
+		major = res;
+
+	return mmc_register_driver(&mmc_driver);
+
+ out:
+	return res;
+}
+
+static void __exit mmc_blk_exit(void)
+{
+	mmc_unregister_driver(&mmc_driver);
+	unregister_blkdev(major, "mmc");
+}
+
+module_init(mmc_blk_init);
+module_exit(mmc_blk_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
+
+module_param(major, int, 0444);
+MODULE_PARM_DESC(major, "specify the major device number for MMC block driver");
diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
new file mode 100644
index 0000000..2e77963
--- /dev/null
+++ b/drivers/mmc/card/queue.c
@@ -0,0 +1,252 @@
+/*
+ *  linux/drivers/mmc/queue.c
+ *
+ *  Copyright (C) 2003 Russell King, All Rights Reserved.
+ *  Copyright 2006-2007 Pierre Ossman
+ *
+ * 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 "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_req_size / 512);
+	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;
+}
+
+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);
+
+	/* Make sure the queue isn't suspended, as that will deadlock */
+	mmc_queue_resume(mq);
+
+	/* 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);
+	}
+}
+
+/**
+ * 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);
+	}
+}
+
diff --git a/drivers/mmc/card/queue.h b/drivers/mmc/card/queue.h
new file mode 100644
index 0000000..c9f139e
--- /dev/null
+++ b/drivers/mmc/card/queue.h
@@ -0,0 +1,32 @@
+#ifndef MMC_QUEUE_H
+#define MMC_QUEUE_H
+
+struct request;
+struct task_struct;
+
+struct mmc_queue {
+	struct mmc_card		*card;
+	struct task_struct	*thread;
+	struct semaphore	thread_sem;
+	unsigned int		flags;
+	struct request		*req;
+	int			(*prep_fn)(struct mmc_queue *, struct request *);
+	int			(*issue_fn)(struct mmc_queue *, struct request *);
+	void			*data;
+	struct request_queue	*queue;
+	struct scatterlist	*sg;
+};
+
+struct mmc_io_request {
+	struct request		*rq;
+	int			num;
+	struct mmc_command	selcmd;		/* mmc_queue private */
+	struct mmc_command	cmd[4];		/* max 4 commands */
+};
+
+extern int mmc_init_queue(struct mmc_queue *, struct mmc_card *, spinlock_t *);
+extern void mmc_cleanup_queue(struct mmc_queue *);
+extern void mmc_queue_suspend(struct mmc_queue *);
+extern void mmc_queue_resume(struct mmc_queue *);
+
+#endif