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-rw-r--r--drivers/mmc/card/Kconfig17
-rw-r--r--drivers/mmc/card/Makefile11
-rw-r--r--drivers/mmc/card/block.c665
-rw-r--r--drivers/mmc/card/queue.c252
-rw-r--r--drivers/mmc/card/queue.h32
5 files changed, 977 insertions, 0 deletions
diff --git a/drivers/mmc/card/Kconfig b/drivers/mmc/card/Kconfig
new file mode 100644
index 00000000000..01a9fd376a1
--- /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 00000000000..cf8c939867f
--- /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 00000000000..d24ab234394
--- /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 00000000000..2e77963db33
--- /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 00000000000..c9f139e764f
--- /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
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-06 21:13:53 +0000