mmc: Move queue functions to mmc_block

The mmc block queue functions are tailored for the mmc_block
driver, so move those functions into that module.

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

1 files changed, 668 insertions, 0 deletions

diff --git a/drivers/mmc/block.c b/drivers/mmc/block.c
new file mode 100644
index 000000000000..8eba037a18e0
--- /dev/null
+++ b/drivers/mmc/block.c
@@ -0,0 +1,668 @@
+/*
+ * 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/protocol.h>
+#include <linux/mmc/host.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;
+
+        if (mmc_card_claim_host(card))
+                goto flush_queue;
+
+        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_card_release_host(card);
+
+        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);
+        }
+
+flush_queue:
+
+        mmc_card_release_host(card);
+
+        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_card_claim_host(card);
+        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_card_release_host(card);
+
+        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");