diff options
Diffstat (limited to 'linux-2.4.x/drivers/mtd/mtdblock.c')
| -rw-r--r-- | linux-2.4.x/drivers/mtd/mtdblock.c | 535 |
1 files changed, 109 insertions, 426 deletions
diff --git a/linux-2.4.x/drivers/mtd/mtdblock.c b/linux-2.4.x/drivers/mtd/mtdblock.c index fdea52d..3605286 100644 --- a/linux-2.4.x/drivers/mtd/mtdblock.c +++ b/linux-2.4.x/drivers/mtd/mtdblock.c @@ -1,76 +1,40 @@ -/* +/* * Direct MTD block device access * - * $Id: mtdblock.c,v 1.51 2001/11/20 11:42:33 dwmw2 Exp $ + * $Id: mtdblock.c,v 1.69 2006/03/29 08:26:27 dwmw2 Exp $ * - * 02-nov-2000 Nicolas Pitre Added read-modify-write with cache + * (C) 2000-2003 Nicolas Pitre <nico@cam.org> + * (C) 1999-2003 David Woodhouse <dwmw2@infradead.org> */ #include <linux/config.h> -#include <linux/types.h> -#include <linux/module.h> +#include <linux/fs.h> +#include <linux/init.h> #include <linux/kernel.h> +#include <linux/module.h> +#include <linux/sched.h> #include <linux/slab.h> +#include <linux/types.h> +#include <linux/vmalloc.h> + #include <linux/mtd/mtd.h> -#include <linux/mtd/compatmac.h> - -#define MAJOR_NR MTD_BLOCK_MAJOR -#define DEVICE_NAME "mtdblock" -#define DEVICE_REQUEST mtdblock_request -#define DEVICE_NR(device) (device) -#define DEVICE_ON(device) -#define DEVICE_OFF(device) -#define DEVICE_NO_RANDOM -#include <linux/blk.h> -/* for old kernels... */ -#ifndef QUEUE_EMPTY -#define QUEUE_EMPTY (!CURRENT) -#endif -#if LINUX_VERSION_CODE < 0x20300 -#define QUEUE_PLUGGED (blk_dev[MAJOR_NR].plug_tq.sync) -#else -#define QUEUE_PLUGGED (blk_dev[MAJOR_NR].request_queue.plugged) -#endif - -#ifdef CONFIG_DEVFS_FS -#include <linux/devfs_fs_kernel.h> -static void mtd_notify_add(struct mtd_info* mtd); -static void mtd_notify_remove(struct mtd_info* mtd); -static struct mtd_notifier notifier = { - mtd_notify_add, - mtd_notify_remove, - NULL -}; -static devfs_handle_t devfs_dir_handle = NULL; -static devfs_handle_t devfs_rw_handle[MAX_MTD_DEVICES]; -#endif +#include <linux/mtd/blktrans.h> +#include <linux/mutex.h> + static struct mtdblk_dev { - struct mtd_info *mtd; /* Locked */ + struct mtd_info *mtd; int count; - struct semaphore cache_sem; + struct mutex cache_mutex; unsigned char *cache_data; unsigned long cache_offset; unsigned int cache_size; enum { STATE_EMPTY, STATE_CLEAN, STATE_DIRTY } cache_state; } *mtdblks[MAX_MTD_DEVICES]; -static spinlock_t mtdblks_lock; - -static int mtd_sizes[MAX_MTD_DEVICES]; -static int mtd_blksizes[MAX_MTD_DEVICES]; - -#if LINUX_VERSION_CODE < KERNEL_VERSION(2,4,14) -#define BLK_INC_USE_COUNT MOD_INC_USE_COUNT -#define BLK_DEC_USE_COUNT MOD_DEC_USE_COUNT -#else -#define BLK_INC_USE_COUNT do {} while(0) -#define BLK_DEC_USE_COUNT do {} while(0) -#endif - /* * Cache stuff... - * + * * Since typical flash erasable sectors are much larger than what Linux's * buffer cache can handle, we must implement read-modify-write on flash * sectors for each block write requests. To avoid over-erasing flash sectors @@ -84,7 +48,7 @@ static void erase_callback(struct erase_info *done) wake_up(wait_q); } -static int erase_write (struct mtd_info *mtd, unsigned long pos, +static int erase_write (struct mtd_info *mtd, unsigned long pos, int len, const char *buf) { struct erase_info erase; @@ -142,18 +106,18 @@ static int write_cached_data (struct mtdblk_dev *mtdblk) return 0; DEBUG(MTD_DEBUG_LEVEL2, "mtdblock: writing cached data for \"%s\" " - "at 0x%lx, size 0x%x\n", mtd->name, + "at 0x%lx, size 0x%x\n", mtd->name, mtdblk->cache_offset, mtdblk->cache_size); - - ret = erase_write (mtd, mtdblk->cache_offset, + + ret = erase_write (mtd, mtdblk->cache_offset, mtdblk->cache_size, mtdblk->cache_data); if (ret) return ret; /* - * Here we could argably set the cache state to STATE_CLEAN. - * However this could lead to inconsistency since we will not - * be notified if this content is altered on the flash by other + * Here we could argubly set the cache state to STATE_CLEAN. + * However this could lead to inconsistency since we will not + * be notified if this content is altered on the flash by other * means. Let's declare it empty and leave buffering tasks to * the buffer cache instead. */ @@ -162,7 +126,7 @@ static int write_cached_data (struct mtdblk_dev *mtdblk) } -static int do_cached_write (struct mtdblk_dev *mtdblk, unsigned long pos, +static int do_cached_write (struct mtdblk_dev *mtdblk, unsigned long pos, int len, const char *buf) { struct mtd_info *mtd = mtdblk->mtd; @@ -172,7 +136,7 @@ static int do_cached_write (struct mtdblk_dev *mtdblk, unsigned long pos, DEBUG(MTD_DEBUG_LEVEL2, "mtdblock: write on \"%s\" at 0x%lx, size 0x%x\n", mtd->name, pos, len); - + if (!sect_size) return MTD_WRITE (mtd, pos, len, &retlen, buf); @@ -180,11 +144,11 @@ static int do_cached_write (struct mtdblk_dev *mtdblk, unsigned long pos, unsigned long sect_start = (pos/sect_size)*sect_size; unsigned int offset = pos - sect_start; unsigned int size = sect_size - offset; - if( size > len ) + if( size > len ) size = len; if (size == sect_size) { - /* + /* * We are covering a whole sector. Thus there is no * need to bother with the cache while it may still be * useful for other partial writes. @@ -198,7 +162,7 @@ static int do_cached_write (struct mtdblk_dev *mtdblk, unsigned long pos, if (mtdblk->cache_state == STATE_DIRTY && mtdblk->cache_offset != sect_start) { ret = write_cached_data(mtdblk); - if (ret) + if (ret) return ret; } @@ -231,7 +195,7 @@ static int do_cached_write (struct mtdblk_dev *mtdblk, unsigned long pos, } -static int do_cached_read (struct mtdblk_dev *mtdblk, unsigned long pos, +static int do_cached_read (struct mtdblk_dev *mtdblk, unsigned long pos, int len, char *buf) { struct mtd_info *mtd = mtdblk->mtd; @@ -239,9 +203,9 @@ static int do_cached_read (struct mtdblk_dev *mtdblk, unsigned long pos, size_t retlen; int ret; - DEBUG(MTD_DEBUG_LEVEL2, "mtdblock: read on \"%s\" at 0x%lx, size 0x%x\n", + DEBUG(MTD_DEBUG_LEVEL2, "mtdblock: read on \"%s\" at 0x%lx, size 0x%x\n", mtd->name, pos, len); - + if (!sect_size) return MTD_READ (mtd, pos, len, &retlen, buf); @@ -249,7 +213,7 @@ static int do_cached_read (struct mtdblk_dev *mtdblk, unsigned long pos, unsigned long sect_start = (pos/sect_size)*sect_size; unsigned int offset = pos - sect_start; unsigned int size = sect_size - offset; - if (size > len) + if (size > len) size = len; /* @@ -277,433 +241,152 @@ static int do_cached_read (struct mtdblk_dev *mtdblk, unsigned long pos, return 0; } +static int mtdblock_readsect(struct mtd_blktrans_dev *dev, + unsigned long block, char *buf) +{ + struct mtdblk_dev *mtdblk = mtdblks[dev->devnum]; + return do_cached_read(mtdblk, block<<9, 512, buf); +} +static int mtdblock_writesect(struct mtd_blktrans_dev *dev, + unsigned long block, char *buf) +{ + struct mtdblk_dev *mtdblk = mtdblks[dev->devnum]; + if (unlikely(!mtdblk->cache_data && mtdblk->cache_size)) { + mtdblk->cache_data = vmalloc(mtdblk->mtd->erasesize); + if (!mtdblk->cache_data) + return -EINTR; + /* -EINTR is not really correct, but it is the best match + * documented in man 2 write for all cases. We could also + * return -EAGAIN sometimes, but why bother? + */ + } + return do_cached_write(mtdblk, block<<9, 512, buf); +} -static int mtdblock_open(struct inode *inode, struct file *file) +static int mtdblock_open(struct mtd_blktrans_dev *mbd) { struct mtdblk_dev *mtdblk; - struct mtd_info *mtd; - int dev; + struct mtd_info *mtd = mbd->mtd; + int dev = mbd->devnum; DEBUG(MTD_DEBUG_LEVEL1,"mtdblock_open\n"); - - if (!inode) - return -EINVAL; - - dev = MINOR(inode->i_rdev); - if (dev >= MAX_MTD_DEVICES) - return -EINVAL; - - BLK_INC_USE_COUNT; - - mtd = get_mtd_device(NULL, dev); - if (!mtd) - return -ENODEV; - if (MTD_ABSENT == mtd->type) { - put_mtd_device(mtd); - BLK_DEC_USE_COUNT; - return -ENODEV; - } - - spin_lock(&mtdblks_lock); - /* If it's already open, no need to piss about. */ if (mtdblks[dev]) { mtdblks[dev]->count++; - spin_unlock(&mtdblks_lock); return 0; } - - /* OK, it's not open. Try to find it */ - - /* First we have to drop the lock, because we have to - to things which might sleep. - */ - spin_unlock(&mtdblks_lock); + /* OK, it's not open. Create cache info for it */ mtdblk = kmalloc(sizeof(struct mtdblk_dev), GFP_KERNEL); - if (!mtdblk) { - put_mtd_device(mtd); - BLK_DEC_USE_COUNT; + if (!mtdblk) return -ENOMEM; - } + memset(mtdblk, 0, sizeof(*mtdblk)); mtdblk->count = 1; mtdblk->mtd = mtd; - init_MUTEX (&mtdblk->cache_sem); + mutex_init(&mtdblk->cache_mutex); mtdblk->cache_state = STATE_EMPTY; if ((mtdblk->mtd->flags & MTD_CAP_RAM) != MTD_CAP_RAM && mtdblk->mtd->erasesize) { mtdblk->cache_size = mtdblk->mtd->erasesize; - mtdblk->cache_data = vmalloc(mtdblk->mtd->erasesize); - if (!mtdblk->cache_data) { - put_mtd_device(mtdblk->mtd); - kfree(mtdblk); - BLK_DEC_USE_COUNT; - return -ENOMEM; - } - } - - /* OK, we've created a new one. Add it to the list. */ - - spin_lock(&mtdblks_lock); - - if (mtdblks[dev]) { - /* Another CPU made one at the same time as us. */ - mtdblks[dev]->count++; - spin_unlock(&mtdblks_lock); - put_mtd_device(mtdblk->mtd); - vfree(mtdblk->cache_data); - kfree(mtdblk); - return 0; + mtdblk->cache_data = NULL; } mtdblks[dev] = mtdblk; - mtd_sizes[dev] = mtdblk->mtd->size/1024; - if (mtdblk->mtd->erasesize) - mtd_blksizes[dev] = mtdblk->mtd->erasesize; - if (mtd_blksizes[dev] > PAGE_SIZE) - mtd_blksizes[dev] = PAGE_SIZE; - set_device_ro (inode->i_rdev, !(mtdblk->mtd->flags & MTD_WRITEABLE)); - - spin_unlock(&mtdblks_lock); - + DEBUG(MTD_DEBUG_LEVEL1, "ok\n"); return 0; } -static release_t mtdblock_release(struct inode *inode, struct file *file) +static int mtdblock_release(struct mtd_blktrans_dev *mbd) { - int dev; - struct mtdblk_dev *mtdblk; - DEBUG(MTD_DEBUG_LEVEL1, "mtdblock_release\n"); - - if (inode == NULL) - release_return(-ENODEV); + int dev = mbd->devnum; + struct mtdblk_dev *mtdblk = mtdblks[dev]; - dev = MINOR(inode->i_rdev); - mtdblk = mtdblks[dev]; + DEBUG(MTD_DEBUG_LEVEL1, "mtdblock_release\n"); - down(&mtdblk->cache_sem); + mutex_lock(&mtdblk->cache_mutex); write_cached_data(mtdblk); - up(&mtdblk->cache_sem); + mutex_unlock(&mtdblk->cache_mutex); - spin_lock(&mtdblks_lock); if (!--mtdblk->count) { /* It was the last usage. Free the device */ mtdblks[dev] = NULL; - spin_unlock(&mtdblks_lock); if (mtdblk->mtd->sync) mtdblk->mtd->sync(mtdblk->mtd); - put_mtd_device(mtdblk->mtd); vfree(mtdblk->cache_data); kfree(mtdblk); - } else { - spin_unlock(&mtdblks_lock); } - DEBUG(MTD_DEBUG_LEVEL1, "ok\n"); - BLK_DEC_USE_COUNT; - release_return(0); -} - - -/* - * This is a special request_fn because it is executed in a process context - * to be able to sleep independently of the caller. The io_request_lock - * is held upon entry and exit. - * The head of our request queue is considered active so there is no need - * to dequeue requests before we are done. - */ -static void handle_mtdblock_request(void) -{ - struct request *req; - struct mtdblk_dev *mtdblk; - unsigned int res; - - for (;;) { - INIT_REQUEST; - req = CURRENT; - spin_unlock_irq(&io_request_lock); - mtdblk = mtdblks[MINOR(req->rq_dev)]; - res = 0; - - if (MINOR(req->rq_dev) >= MAX_MTD_DEVICES) - panic(__FUNCTION__": minor out of bound"); - - if ((req->sector + req->current_nr_sectors) > (mtdblk->mtd->size >> 9)) - goto end_req; - - // Handle the request - switch (req->cmd) - { - int err; - - case READ: - down(&mtdblk->cache_sem); - err = do_cached_read (mtdblk, req->sector << 9, - req->current_nr_sectors << 9, - req->buffer); - up(&mtdblk->cache_sem); - if (!err) - res = 1; - break; - - case WRITE: - // Read only device - if ( !(mtdblk->mtd->flags & MTD_WRITEABLE) ) - break; - - // Do the write - down(&mtdblk->cache_sem); - err = do_cached_write (mtdblk, req->sector << 9, - req->current_nr_sectors << 9, - req->buffer); - up(&mtdblk->cache_sem); - if (!err) - res = 1; - break; - } - -end_req: - spin_lock_irq(&io_request_lock); - end_request(res); - } + return 0; } -static volatile int leaving = 0; -static DECLARE_MUTEX_LOCKED(thread_sem); -static DECLARE_WAIT_QUEUE_HEAD(thr_wq); - -int mtdblock_thread(void *dummy) +static int mtdblock_flush(struct mtd_blktrans_dev *dev) { - struct task_struct *tsk = current; - DECLARE_WAITQUEUE(wait, tsk); - - tsk->session = 1; - tsk->pgrp = 1; - /* we might get involved when memory gets low, so use PF_MEMALLOC */ - tsk->flags |= PF_MEMALLOC; - strcpy(tsk->comm, "mtdblockd"); - tsk->tty = NULL; - spin_lock_irq(&tsk->sigmask_lock); - sigfillset(&tsk->blocked); - recalc_sigpending(tsk); - spin_unlock_irq(&tsk->sigmask_lock); - exit_mm(tsk); - exit_files(tsk); - exit_sighand(tsk); - exit_fs(tsk); - - while (!leaving) { - add_wait_queue(&thr_wq, &wait); - set_current_state(TASK_INTERRUPTIBLE); - spin_lock_irq(&io_request_lock); - if (QUEUE_EMPTY || QUEUE_PLUGGED) { - spin_unlock_irq(&io_request_lock); - schedule(); - remove_wait_queue(&thr_wq, &wait); - } else { - remove_wait_queue(&thr_wq, &wait); - set_current_state(TASK_RUNNING); - handle_mtdblock_request(); - spin_unlock_irq(&io_request_lock); - } - } + struct mtdblk_dev *mtdblk = mtdblks[dev->devnum]; + + mutex_lock(&mtdblk->cache_mutex); + write_cached_data(mtdblk); + mutex_unlock(&mtdblk->cache_mutex); - up(&thread_sem); + if (mtdblk->mtd->sync) + mtdblk->mtd->sync(mtdblk->mtd); return 0; } -#if LINUX_VERSION_CODE < 0x20300 -#define RQFUNC_ARG void -#else -#define RQFUNC_ARG request_queue_t *q -#endif - -static void mtdblock_request(RQFUNC_ARG) +static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd) { - /* Don't do anything, except wake the thread if necessary */ - wake_up(&thr_wq); -} + struct mtd_blktrans_dev *dev = kmalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + return; -static int mtdblock_ioctl(struct inode * inode, struct file * file, - unsigned int cmd, unsigned long arg) -{ - struct mtdblk_dev *mtdblk; + memset(dev, 0, sizeof(*dev)); - mtdblk = mtdblks[MINOR(inode->i_rdev)]; + dev->mtd = mtd; + dev->devnum = mtd->index; + dev->blksize = 512; + dev->size = mtd->size >> 9; + dev->tr = tr; -#ifdef PARANOIA - if (!mtdblk) - BUG(); -#endif - - switch (cmd) { - case BLKGETSIZE: /* Return device size */ - return put_user((mtdblk->mtd->size >> 9), (unsigned long *) arg); - -#ifdef BLKGETSIZE64 - case BLKGETSIZE64: - return put_user((u64)mtdblk->mtd->size, (u64 *)arg); -#endif - - case BLKFLSBUF: -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,2,0) - if(!capable(CAP_SYS_ADMIN)) - return -EACCES; -#endif - fsync_dev(inode->i_rdev); - invalidate_buffers(inode->i_rdev); - down(&mtdblk->cache_sem); - write_cached_data(mtdblk); - up(&mtdblk->cache_sem); - if (mtdblk->mtd->sync) - mtdblk->mtd->sync(mtdblk->mtd); - return 0; + if (!(mtd->flags & MTD_WRITEABLE)) + dev->readonly = 1; - default: - return -EINVAL; - } + add_mtd_blktrans_dev(dev); } - -#ifdef MAGIC_ROM_PTR -static int -mtdblock_romptr(kdev_t dev, struct vm_area_struct * vma) +static void mtdblock_remove_dev(struct mtd_blktrans_dev *dev) { - struct mtd_info *mtd; - u_char *ptr; - size_t len; - - mtd = __get_mtd_device(NULL, MINOR(dev)); - - if (!mtd->point) - return -ENOSYS; /* Can't do it, No function to point to correct addr */ - - if ((*mtd->point)(mtd,vma->vm_offset,vma->vm_end-vma->vm_start,&len,&ptr) != 0) - return -ENOSYS; - - vma->vm_start = (unsigned long) ptr; - vma->vm_end = vma->vm_start + len; - return 0; + del_mtd_blktrans_dev(dev); + kfree(dev); } -#endif - -#if LINUX_VERSION_CODE < 0x20326 -static struct file_operations mtd_fops = -{ - open: mtdblock_open, - ioctl: mtdblock_ioctl, - release: mtdblock_release, - read: block_read, -#ifdef MAGIC_ROM_PTR - romptr: mtdblock_romptr, -#endif - write: block_write -}; -#else -static struct block_device_operations mtd_fops = -{ -#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,14) - owner: THIS_MODULE, -#endif - open: mtdblock_open, - release: mtdblock_release, -#ifdef MAGIC_ROM_PTR - romptr: mtdblock_romptr, -#endif - ioctl: mtdblock_ioctl +static struct mtd_blktrans_ops mtdblock_tr = { + .name = "mtdblock", + .major = 31, + .part_bits = 0, + .open = mtdblock_open, + .flush = mtdblock_flush, + .release = mtdblock_release, + .readsect = mtdblock_readsect, + .writesect = mtdblock_writesect, + .add_mtd = mtdblock_add_mtd, + .remove_dev = mtdblock_remove_dev, + .owner = THIS_MODULE, }; -#endif - -#ifdef CONFIG_DEVFS_FS -/* Notification that a new device has been added. Create the devfs entry for - * it. */ - -static void mtd_notify_add(struct mtd_info* mtd) -{ - char name[8]; - if (!mtd || mtd->type == MTD_ABSENT) - return; - - sprintf(name, "%d", mtd->index); - devfs_rw_handle[mtd->index] = devfs_register(devfs_dir_handle, name, - DEVFS_FL_DEFAULT, MTD_BLOCK_MAJOR, mtd->index, - S_IFBLK | S_IRUGO | S_IWUGO, - &mtd_fops, NULL); -} - -static void mtd_notify_remove(struct mtd_info* mtd) -{ - if (!mtd || mtd->type == MTD_ABSENT) - return; - - devfs_unregister(devfs_rw_handle[mtd->index]); -} -#endif - -int __init init_mtdblock(void) +static int __init init_mtdblock(void) { - int i; - - spin_lock_init(&mtdblks_lock); -#ifdef CONFIG_DEVFS_FS - if (devfs_register_blkdev(MTD_BLOCK_MAJOR, DEVICE_NAME, &mtd_fops)) - { - printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n", - MTD_BLOCK_MAJOR); - return -EAGAIN; - } - - devfs_dir_handle = devfs_mk_dir(NULL, DEVICE_NAME, NULL); - register_mtd_user(¬ifier); -#else - if (register_blkdev(MAJOR_NR,DEVICE_NAME,&mtd_fops)) { - printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n", - MTD_BLOCK_MAJOR); - return -EAGAIN; - } -#endif - DEBUG(MTD_DEBUG_LEVEL3, - "init_mtdblock: allocated major number %d.\n", MTD_BLOCK_MAJOR); - - /* We fill it in at open() time. */ - for (i=0; i< MAX_MTD_DEVICES; i++) { - mtd_sizes[i] = 0; - mtd_blksizes[i] = BLOCK_SIZE; - } - init_waitqueue_head(&thr_wq); - /* Allow the block size to default to BLOCK_SIZE. */ - blksize_size[MAJOR_NR] = mtd_blksizes; - blk_size[MAJOR_NR] = mtd_sizes; - - blk_init_queue(BLK_DEFAULT_QUEUE(MAJOR_NR), &mtdblock_request); - kernel_thread (mtdblock_thread, NULL, CLONE_FS|CLONE_FILES|CLONE_SIGHAND); - return 0; + return register_mtd_blktrans(&mtdblock_tr); } static void __exit cleanup_mtdblock(void) { - leaving = 1; - wake_up(&thr_wq); - down(&thread_sem); -#ifdef CONFIG_DEVFS_FS - unregister_mtd_user(¬ifier); - devfs_unregister(devfs_dir_handle); - devfs_unregister_blkdev(MTD_BLOCK_MAJOR, DEVICE_NAME); -#else - unregister_blkdev(MAJOR_NR,DEVICE_NAME); -#endif - blk_cleanup_queue(BLK_DEFAULT_QUEUE(MAJOR_NR)); - blksize_size[MAJOR_NR] = NULL; - blk_size[MAJOR_NR] = NULL; + deregister_mtd_blktrans(&mtdblock_tr); } module_init(init_mtdblock); |