Merge branch 'for-2.6.33' of git://git.kernel.dk/linux-2.6-block
[safe/jmp/linux-2.6] / drivers / mtd / mtd_blkdevs.c
index d6cb3d1..64e2b37 100644 (file)
@@ -1,6 +1,4 @@
 /*
- * $Id: mtd_blkdevs.c,v 1.26 2005/07/29 19:42:04 tpoynor Exp $
- *
  * (C) 2003 David Woodhouse <dwmw2@infradead.org>
  *
  * Interface to Linux 2.5 block layer for MTD 'translation layers'.
 #include <linux/mtd/mtd.h>
 #include <linux/blkdev.h>
 #include <linux/blkpg.h>
+#include <linux/freezer.h>
 #include <linux/spinlock.h>
 #include <linux/hdreg.h>
 #include <linux/init.h>
-#include <asm/semaphore.h>
+#include <linux/mutex.h>
+#include <linux/kthread.h>
 #include <asm/uaccess.h>
 
-static LIST_HEAD(blktrans_majors);
+#include "mtdcore.h"
 
-extern struct semaphore mtd_table_mutex;
-extern struct mtd_info *mtd_table[];
+static LIST_HEAD(blktrans_majors);
 
 struct mtd_blkcore_priv {
-       struct completion thread_dead;
-       int exiting;
-       wait_queue_head_t thread_wq;
+       struct task_struct *thread;
        struct request_queue *rq;
        spinlock_t queue_lock;
 };
@@ -42,35 +39,42 @@ static int do_blktrans_request(struct mtd_blktrans_ops *tr,
        unsigned long block, nsect;
        char *buf;
 
-       block = req->sector;
-       nsect = req->current_nr_sectors;
+       block = blk_rq_pos(req) << 9 >> tr->blkshift;
+       nsect = blk_rq_cur_bytes(req) >> tr->blkshift;
+
        buf = req->buffer;
 
-       if (!(req->flags & REQ_CMD))
-               return 0;
+       if (!blk_fs_request(req))
+               return -EIO;
 
-       if (block + nsect > get_capacity(req->rq_disk))
-               return 0;
+       if (blk_rq_pos(req) + blk_rq_cur_sectors(req) >
+           get_capacity(req->rq_disk))
+               return -EIO;
+
+       if (blk_discard_rq(req))
+               return tr->discard(dev, block, nsect);
 
        switch(rq_data_dir(req)) {
        case READ:
-               for (; nsect > 0; nsect--, block++, buf += 512)
+               for (; nsect > 0; nsect--, block++, buf += tr->blksize)
                        if (tr->readsect(dev, block, buf))
-                               return 0;
-               return 1;
+                               return -EIO;
+               rq_flush_dcache_pages(req);
+               return 0;
 
        case WRITE:
                if (!tr->writesect)
-                       return 0;
+                       return -EIO;
 
-               for (; nsect > 0; nsect--, block++, buf += 512)
+               rq_flush_dcache_pages(req);
+               for (; nsect > 0; nsect--, block++, buf += tr->blksize)
                        if (tr->writesect(dev, block, buf))
-                               return 0;
-               return 1;
+                               return -EIO;
+               return 0;
 
        default:
-               printk(KERN_NOTICE "Unknown request %ld\n", rq_data_dir(req));
-               return 0;
+               printk(KERN_NOTICE "Unknown request %u\n", rq_data_dir(req));
+               return -EIO;
        }
 }
 
@@ -78,42 +82,22 @@ static int mtd_blktrans_thread(void *arg)
 {
        struct mtd_blktrans_ops *tr = arg;
        struct request_queue *rq = tr->blkcore_priv->rq;
+       struct request *req = NULL;
 
        /* we might get involved when memory gets low, so use PF_MEMALLOC */
-       current->flags |= PF_MEMALLOC | PF_NOFREEZE;
-
-       daemonize("%sd", tr->name);
-
-       /* daemonize() doesn't do this for us since some kernel threads
-          actually want to deal with signals. We can't just call 
-          exit_sighand() since that'll cause an oops when we finally
-          do exit. */
-       spin_lock_irq(&current->sighand->siglock);
-       sigfillset(&current->blocked);
-       recalc_sigpending();
-       spin_unlock_irq(&current->sighand->siglock);
+       current->flags |= PF_MEMALLOC;
 
        spin_lock_irq(rq->queue_lock);
-               
-       while (!tr->blkcore_priv->exiting) {
-               struct request *req;
-               struct mtd_blktrans_dev *dev;
-               int res = 0;
-               DECLARE_WAITQUEUE(wait, current);
 
-               req = elv_next_request(rq);
+       while (!kthread_should_stop()) {
+               struct mtd_blktrans_dev *dev;
+               int res;
 
-               if (!req) {
-                       add_wait_queue(&tr->blkcore_priv->thread_wq, &wait);
+               if (!req && !(req = blk_fetch_request(rq))) {
                        set_current_state(TASK_INTERRUPTIBLE);
-
                        spin_unlock_irq(rq->queue_lock);
-
                        schedule();
-                       remove_wait_queue(&tr->blkcore_priv->thread_wq, &wait);
-
                        spin_lock_irq(rq->queue_lock);
-
                        continue;
                }
 
@@ -122,42 +106,44 @@ static int mtd_blktrans_thread(void *arg)
 
                spin_unlock_irq(rq->queue_lock);
 
-               down(&dev->sem);
+               mutex_lock(&dev->lock);
                res = do_blktrans_request(tr, dev, req);
-               up(&dev->sem);
+               mutex_unlock(&dev->lock);
 
                spin_lock_irq(rq->queue_lock);
 
-               end_request(req, res);
+               if (!__blk_end_request_cur(req, res))
+                       req = NULL;
        }
+
+       if (req)
+               __blk_end_request_all(req, -EIO);
+
        spin_unlock_irq(rq->queue_lock);
 
-       complete_and_exit(&tr->blkcore_priv->thread_dead, 0);
+       return 0;
 }
 
 static void mtd_blktrans_request(struct request_queue *rq)
 {
        struct mtd_blktrans_ops *tr = rq->queuedata;
-       wake_up(&tr->blkcore_priv->thread_wq);
+       wake_up_process(tr->blkcore_priv->thread);
 }
 
 
-static int blktrans_open(struct inode *i, struct file *f)
+static int blktrans_open(struct block_device *bdev, fmode_t mode)
 {
-       struct mtd_blktrans_dev *dev;
-       struct mtd_blktrans_ops *tr;
+       struct mtd_blktrans_dev *dev = bdev->bd_disk->private_data;
+       struct mtd_blktrans_ops *tr = dev->tr;
        int ret = -ENODEV;
 
-       dev = i->i_bdev->bd_disk->private_data;
-       tr = dev->tr;
-
-       if (!try_module_get(dev->mtd->owner))
+       if (!get_mtd_device(NULL, dev->mtd->index))
                goto out;
 
        if (!try_module_get(tr->owner))
                goto out_tr;
 
-       /* FIXME: Locking. A hot pluggable device can go away 
+       /* FIXME: Locking. A hot pluggable device can go away
           (del_mtd_device can be called for it) without its module
           being unloaded. */
        dev->mtd->usecount++;
@@ -165,7 +151,7 @@ static int blktrans_open(struct inode *i, struct file *f)
        ret = 0;
        if (tr->open && (ret = tr->open(dev))) {
                dev->mtd->usecount--;
-               module_put(dev->mtd->owner);
+               put_mtd_device(dev->mtd);
        out_tr:
                module_put(tr->owner);
        }
@@ -173,32 +159,37 @@ static int blktrans_open(struct inode *i, struct file *f)
        return ret;
 }
 
-static int blktrans_release(struct inode *i, struct file *f)
+static int blktrans_release(struct gendisk *disk, fmode_t mode)
 {
-       struct mtd_blktrans_dev *dev;
-       struct mtd_blktrans_ops *tr;
+       struct mtd_blktrans_dev *dev = disk->private_data;
+       struct mtd_blktrans_ops *tr = dev->tr;
        int ret = 0;
 
-       dev = i->i_bdev->bd_disk->private_data;
-       tr = dev->tr;
-
        if (tr->release)
                ret = tr->release(dev);
 
        if (!ret) {
                dev->mtd->usecount--;
-               module_put(dev->mtd->owner);
+               put_mtd_device(dev->mtd);
                module_put(tr->owner);
        }
 
        return ret;
 }
 
+static int blktrans_getgeo(struct block_device *bdev, struct hd_geometry *geo)
+{
+       struct mtd_blktrans_dev *dev = bdev->bd_disk->private_data;
 
-static int blktrans_ioctl(struct inode *inode, struct file *file, 
+       if (dev->tr->getgeo)
+               return dev->tr->getgeo(dev, geo);
+       return -ENOTTY;
+}
+
+static int blktrans_ioctl(struct block_device *bdev, fmode_t mode,
                              unsigned int cmd, unsigned long arg)
 {
-       struct mtd_blktrans_dev *dev = inode->i_bdev->bd_disk->private_data;
+       struct mtd_blktrans_dev *dev = bdev->bd_disk->private_data;
        struct mtd_blktrans_ops *tr = dev->tr;
 
        switch (cmd) {
@@ -207,48 +198,32 @@ static int blktrans_ioctl(struct inode *inode, struct file *file,
                        return tr->flush(dev);
                /* The core code did the work, we had nothing to do. */
                return 0;
-
-       case HDIO_GETGEO:
-               if (tr->getgeo) {
-                       struct hd_geometry g;
-                       int ret;
-
-                       memset(&g, 0, sizeof(g));
-                       ret = tr->getgeo(dev, &g);
-                       if (ret)
-                               return ret;
-
-                       g.start = get_start_sect(inode->i_bdev);
-                       if (copy_to_user((void __user *)arg, &g, sizeof(g)))
-                               return -EFAULT;
-                       return 0;
-               } /* else */
        default:
                return -ENOTTY;
        }
 }
 
-struct block_device_operations mtd_blktrans_ops = {
+static const struct block_device_operations mtd_blktrans_ops = {
        .owner          = THIS_MODULE,
        .open           = blktrans_open,
        .release        = blktrans_release,
-       .ioctl          = blktrans_ioctl,
+       .locked_ioctl   = blktrans_ioctl,
+       .getgeo         = blktrans_getgeo,
 };
 
 int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 {
        struct mtd_blktrans_ops *tr = new->tr;
-       struct list_head *this;
+       struct mtd_blktrans_dev *d;
        int last_devnum = -1;
        struct gendisk *gd;
 
-       if (!down_trylock(&mtd_table_mutex)) {
-               up(&mtd_table_mutex);
+       if (mutex_trylock(&mtd_table_mutex)) {
+               mutex_unlock(&mtd_table_mutex);
                BUG();
        }
 
-       list_for_each(this, &tr->devs) {
-               struct mtd_blktrans_dev *d = list_entry(this, struct mtd_blktrans_dev, list);
+       list_for_each_entry(d, &tr->devs, list) {
                if (new->devnum == -1) {
                        /* Use first free number */
                        if (d->devnum != last_devnum+1) {
@@ -264,7 +239,7 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
                        /* Required number was free */
                        list_add_tail(&new->list, &d->list);
                        goto added;
-               } 
+               }
                last_devnum = d->devnum;
        }
        if (new->devnum == -1)
@@ -274,9 +249,9 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
                return -EBUSY;
        }
 
-       init_MUTEX(&new->sem);
        list_add_tail(&new->list, &tr->devs);
  added:
+       mutex_init(&new->lock);
        if (!tr->writesect)
                new->readonly = 1;
 
@@ -288,7 +263,7 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
        gd->major = tr->major;
        gd->first_minor = (new->devnum) << tr->part_bits;
        gd->fops = &mtd_blktrans_ops;
-       
+
        if (tr->part_bits)
                if (new->devnum < 26)
                        snprintf(gd->disk_name, sizeof(gd->disk_name),
@@ -304,24 +279,25 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 
        /* 2.5 has capacity in units of 512 bytes while still
           having BLOCK_SIZE_BITS set to 10. Just to keep us amused. */
-       set_capacity(gd, (new->size * new->blksize) >> 9);
+       set_capacity(gd, (new->size * tr->blksize) >> 9);
 
        gd->private_data = new;
        new->blkcore_priv = gd;
        gd->queue = tr->blkcore_priv->rq;
+       gd->driverfs_dev = &new->mtd->dev;
 
        if (new->readonly)
                set_disk_ro(gd, 1);
 
        add_disk(gd);
-       
+
        return 0;
 }
 
 int del_mtd_blktrans_dev(struct mtd_blktrans_dev *old)
 {
-       if (!down_trylock(&mtd_table_mutex)) {
-               up(&mtd_table_mutex);
+       if (mutex_trylock(&mtd_table_mutex)) {
+               mutex_unlock(&mtd_table_mutex);
                BUG();
        }
 
@@ -329,94 +305,89 @@ int del_mtd_blktrans_dev(struct mtd_blktrans_dev *old)
 
        del_gendisk(old->blkcore_priv);
        put_disk(old->blkcore_priv);
-               
+
        return 0;
 }
 
 static void blktrans_notify_remove(struct mtd_info *mtd)
 {
-       struct list_head *this, *this2, *next;
-
-       list_for_each(this, &blktrans_majors) {
-               struct mtd_blktrans_ops *tr = list_entry(this, struct mtd_blktrans_ops, list);
-
-               list_for_each_safe(this2, next, &tr->devs) {
-                       struct mtd_blktrans_dev *dev = list_entry(this2, struct mtd_blktrans_dev, list);
+       struct mtd_blktrans_ops *tr;
+       struct mtd_blktrans_dev *dev, *next;
 
+       list_for_each_entry(tr, &blktrans_majors, list)
+               list_for_each_entry_safe(dev, next, &tr->devs, list)
                        if (dev->mtd == mtd)
                                tr->remove_dev(dev);
-               }
-       }
 }
 
 static void blktrans_notify_add(struct mtd_info *mtd)
 {
-       struct list_head *this;
+       struct mtd_blktrans_ops *tr;
 
        if (mtd->type == MTD_ABSENT)
                return;
 
-       list_for_each(this, &blktrans_majors) {
-               struct mtd_blktrans_ops *tr = list_entry(this, struct mtd_blktrans_ops, list);
-
+       list_for_each_entry(tr, &blktrans_majors, list)
                tr->add_mtd(tr, mtd);
-       }
-
 }
 
 static struct mtd_notifier blktrans_notifier = {
        .add = blktrans_notify_add,
        .remove = blktrans_notify_remove,
 };
-      
+
 int register_mtd_blktrans(struct mtd_blktrans_ops *tr)
 {
        int ret, i;
 
-       /* Register the notifier if/when the first device type is 
+       /* Register the notifier if/when the first device type is
           registered, to prevent the link/init ordering from fucking
           us over. */
        if (!blktrans_notifier.list.next)
                register_mtd_user(&blktrans_notifier);
 
-       tr->blkcore_priv = kmalloc(sizeof(*tr->blkcore_priv), GFP_KERNEL);
+       tr->blkcore_priv = kzalloc(sizeof(*tr->blkcore_priv), GFP_KERNEL);
        if (!tr->blkcore_priv)
                return -ENOMEM;
 
-       memset(tr->blkcore_priv, 0, sizeof(*tr->blkcore_priv));
-
-       down(&mtd_table_mutex);
+       mutex_lock(&mtd_table_mutex);
 
        ret = register_blkdev(tr->major, tr->name);
        if (ret) {
                printk(KERN_WARNING "Unable to register %s block device on major %d: %d\n",
                       tr->name, tr->major, ret);
                kfree(tr->blkcore_priv);
-               up(&mtd_table_mutex);
+               mutex_unlock(&mtd_table_mutex);
                return ret;
        }
        spin_lock_init(&tr->blkcore_priv->queue_lock);
-       init_completion(&tr->blkcore_priv->thread_dead);
-       init_waitqueue_head(&tr->blkcore_priv->thread_wq);
 
        tr->blkcore_priv->rq = blk_init_queue(mtd_blktrans_request, &tr->blkcore_priv->queue_lock);
        if (!tr->blkcore_priv->rq) {
                unregister_blkdev(tr->major, tr->name);
                kfree(tr->blkcore_priv);
-               up(&mtd_table_mutex);
+               mutex_unlock(&mtd_table_mutex);
                return -ENOMEM;
        }
 
        tr->blkcore_priv->rq->queuedata = tr;
+       blk_queue_logical_block_size(tr->blkcore_priv->rq, tr->blksize);
+       if (tr->discard)
+               queue_flag_set_unlocked(QUEUE_FLAG_DISCARD,
+                                       tr->blkcore_priv->rq);
+
+       tr->blkshift = ffs(tr->blksize) - 1;
 
-       ret = kernel_thread(mtd_blktrans_thread, tr, CLONE_KERNEL);
-       if (ret < 0) {
+       tr->blkcore_priv->thread = kthread_run(mtd_blktrans_thread, tr,
+                       "%sd", tr->name);
+       if (IS_ERR(tr->blkcore_priv->thread)) {
+               int ret = PTR_ERR(tr->blkcore_priv->thread);
                blk_cleanup_queue(tr->blkcore_priv->rq);
                unregister_blkdev(tr->major, tr->name);
                kfree(tr->blkcore_priv);
-               up(&mtd_table_mutex);
+               mutex_unlock(&mtd_table_mutex);
                return ret;
-       } 
+       }
 
        INIT_LIST_HEAD(&tr->devs);
        list_add(&tr->list, &blktrans_majors);
@@ -426,39 +397,34 @@ int register_mtd_blktrans(struct mtd_blktrans_ops *tr)
                        tr->add_mtd(tr, mtd_table[i]);
        }
 
-       up(&mtd_table_mutex);
+       mutex_unlock(&mtd_table_mutex);
 
        return 0;
 }
 
 int deregister_mtd_blktrans(struct mtd_blktrans_ops *tr)
 {
-       struct list_head *this, *next;
+       struct mtd_blktrans_dev *dev, *next;
 
-       down(&mtd_table_mutex);
+       mutex_lock(&mtd_table_mutex);
 
        /* Clean up the kernel thread */
-       tr->blkcore_priv->exiting = 1;
-       wake_up(&tr->blkcore_priv->thread_wq);
-       wait_for_completion(&tr->blkcore_priv->thread_dead);
+       kthread_stop(tr->blkcore_priv->thread);
 
        /* Remove it from the list of active majors */
        list_del(&tr->list);
 
-       list_for_each_safe(this, next, &tr->devs) {
-               struct mtd_blktrans_dev *dev = list_entry(this, struct mtd_blktrans_dev, list);
+       list_for_each_entry_safe(dev, next, &tr->devs, list)
                tr->remove_dev(dev);
-       }
 
        blk_cleanup_queue(tr->blkcore_priv->rq);
        unregister_blkdev(tr->major, tr->name);
 
-       up(&mtd_table_mutex);
+       mutex_unlock(&mtd_table_mutex);
 
        kfree(tr->blkcore_priv);
 
-       if (!list_empty(&tr->devs))
-               BUG();
+       BUG_ON(!list_empty(&tr->devs));
        return 0;
 }