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path: root/drivers/mtd/mtdchar.c
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Diffstat (limited to 'drivers/mtd/mtdchar.c')
-rw-r--r--drivers/mtd/mtdchar.c562
1 files changed, 562 insertions, 0 deletions
diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
new file mode 100644
index 00000000000..510ad78312c
--- /dev/null
+++ b/drivers/mtd/mtdchar.c
@@ -0,0 +1,562 @@
+/*
+ * $Id: mtdchar.c,v 1.66 2005/01/05 18:05:11 dwmw2 Exp $
+ *
+ * Character-device access to raw MTD devices.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/compatmac.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <asm/uaccess.h>
+
+#ifdef CONFIG_DEVFS_FS
+#include <linux/devfs_fs_kernel.h>
+
+static void mtd_notify_add(struct mtd_info* mtd)
+{
+ if (!mtd)
+ return;
+
+ devfs_mk_cdev(MKDEV(MTD_CHAR_MAJOR, mtd->index*2),
+ S_IFCHR | S_IRUGO | S_IWUGO, "mtd/%d", mtd->index);
+
+ devfs_mk_cdev(MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1),
+ S_IFCHR | S_IRUGO, "mtd/%dro", mtd->index);
+}
+
+static void mtd_notify_remove(struct mtd_info* mtd)
+{
+ if (!mtd)
+ return;
+ devfs_remove("mtd/%d", mtd->index);
+ devfs_remove("mtd/%dro", mtd->index);
+}
+
+static struct mtd_notifier notifier = {
+ .add = mtd_notify_add,
+ .remove = mtd_notify_remove,
+};
+
+static inline void mtdchar_devfs_init(void)
+{
+ devfs_mk_dir("mtd");
+ register_mtd_user(&notifier);
+}
+
+static inline void mtdchar_devfs_exit(void)
+{
+ unregister_mtd_user(&notifier);
+ devfs_remove("mtd");
+}
+#else /* !DEVFS */
+#define mtdchar_devfs_init() do { } while(0)
+#define mtdchar_devfs_exit() do { } while(0)
+#endif
+
+static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
+{
+ struct mtd_info *mtd = file->private_data;
+
+ switch (orig) {
+ case 0:
+ /* SEEK_SET */
+ file->f_pos = offset;
+ break;
+ case 1:
+ /* SEEK_CUR */
+ file->f_pos += offset;
+ break;
+ case 2:
+ /* SEEK_END */
+ file->f_pos =mtd->size + offset;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (file->f_pos < 0)
+ file->f_pos = 0;
+ else if (file->f_pos >= mtd->size)
+ file->f_pos = mtd->size - 1;
+
+ return file->f_pos;
+}
+
+
+
+static int mtd_open(struct inode *inode, struct file *file)
+{
+ int minor = iminor(inode);
+ int devnum = minor >> 1;
+ struct mtd_info *mtd;
+
+ DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
+
+ if (devnum >= MAX_MTD_DEVICES)
+ return -ENODEV;
+
+ /* You can't open the RO devices RW */
+ if ((file->f_mode & 2) && (minor & 1))
+ return -EACCES;
+
+ mtd = get_mtd_device(NULL, devnum);
+
+ if (!mtd)
+ return -ENODEV;
+
+ if (MTD_ABSENT == mtd->type) {
+ put_mtd_device(mtd);
+ return -ENODEV;
+ }
+
+ file->private_data = mtd;
+
+ /* You can't open it RW if it's not a writeable device */
+ if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
+ put_mtd_device(mtd);
+ return -EACCES;
+ }
+
+ return 0;
+} /* mtd_open */
+
+/*====================================================================*/
+
+static int mtd_close(struct inode *inode, struct file *file)
+{
+ struct mtd_info *mtd;
+
+ DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
+
+ mtd = file->private_data;
+
+ if (mtd->sync)
+ mtd->sync(mtd);
+
+ put_mtd_device(mtd);
+
+ return 0;
+} /* mtd_close */
+
+/* FIXME: This _really_ needs to die. In 2.5, we should lock the
+ userspace buffer down and use it directly with readv/writev.
+*/
+#define MAX_KMALLOC_SIZE 0x20000
+
+static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
+{
+ struct mtd_info *mtd = file->private_data;
+ size_t retlen=0;
+ size_t total_retlen=0;
+ int ret=0;
+ int len;
+ char *kbuf;
+
+ DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
+
+ if (*ppos + count > mtd->size)
+ count = mtd->size - *ppos;
+
+ if (!count)
+ return 0;
+
+ /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
+ and pass them directly to the MTD functions */
+ while (count) {
+ if (count > MAX_KMALLOC_SIZE)
+ len = MAX_KMALLOC_SIZE;
+ else
+ len = count;
+
+ kbuf=kmalloc(len,GFP_KERNEL);
+ if (!kbuf)
+ return -ENOMEM;
+
+ ret = MTD_READ(mtd, *ppos, len, &retlen, kbuf);
+ /* Nand returns -EBADMSG on ecc errors, but it returns
+ * the data. For our userspace tools it is important
+ * to dump areas with ecc errors !
+ * Userspace software which accesses NAND this way
+ * must be aware of the fact that it deals with NAND
+ */
+ if (!ret || (ret == -EBADMSG)) {
+ *ppos += retlen;
+ if (copy_to_user(buf, kbuf, retlen)) {
+ kfree(kbuf);
+ return -EFAULT;
+ }
+ else
+ total_retlen += retlen;
+
+ count -= retlen;
+ buf += retlen;
+ }
+ else {
+ kfree(kbuf);
+ return ret;
+ }
+
+ kfree(kbuf);
+ }
+
+ return total_retlen;
+} /* mtd_read */
+
+static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
+{
+ struct mtd_info *mtd = file->private_data;
+ char *kbuf;
+ size_t retlen;
+ size_t total_retlen=0;
+ int ret=0;
+ int len;
+
+ DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
+
+ if (*ppos == mtd->size)
+ return -ENOSPC;
+
+ if (*ppos + count > mtd->size)
+ count = mtd->size - *ppos;
+
+ if (!count)
+ return 0;
+
+ while (count) {
+ if (count > MAX_KMALLOC_SIZE)
+ len = MAX_KMALLOC_SIZE;
+ else
+ len = count;
+
+ kbuf=kmalloc(len,GFP_KERNEL);
+ if (!kbuf) {
+ printk("kmalloc is null\n");
+ return -ENOMEM;
+ }
+
+ if (copy_from_user(kbuf, buf, len)) {
+ kfree(kbuf);
+ return -EFAULT;
+ }
+
+ ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
+ if (!ret) {
+ *ppos += retlen;
+ total_retlen += retlen;
+ count -= retlen;
+ buf += retlen;
+ }
+ else {
+ kfree(kbuf);
+ return ret;
+ }
+
+ kfree(kbuf);
+ }
+
+ return total_retlen;
+} /* mtd_write */
+
+/*======================================================================
+
+ IOCTL calls for getting device parameters.
+
+======================================================================*/
+static void mtdchar_erase_callback (struct erase_info *instr)
+{
+ wake_up((wait_queue_head_t *)instr->priv);
+}
+
+static int mtd_ioctl(struct inode *inode, struct file *file,
+ u_int cmd, u_long arg)
+{
+ struct mtd_info *mtd = file->private_data;
+ void __user *argp = (void __user *)arg;
+ int ret = 0;
+ u_long size;
+
+ DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
+
+ size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
+ if (cmd & IOC_IN) {
+ if (!access_ok(VERIFY_READ, argp, size))
+ return -EFAULT;
+ }
+ if (cmd & IOC_OUT) {
+ if (!access_ok(VERIFY_WRITE, argp, size))
+ return -EFAULT;
+ }
+
+ switch (cmd) {
+ case MEMGETREGIONCOUNT:
+ if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
+ return -EFAULT;
+ break;
+
+ case MEMGETREGIONINFO:
+ {
+ struct region_info_user ur;
+
+ if (copy_from_user(&ur, argp, sizeof(struct region_info_user)))
+ return -EFAULT;
+
+ if (ur.regionindex >= mtd->numeraseregions)
+ return -EINVAL;
+ if (copy_to_user(argp, &(mtd->eraseregions[ur.regionindex]),
+ sizeof(struct mtd_erase_region_info)))
+ return -EFAULT;
+ break;
+ }
+
+ case MEMGETINFO:
+ if (copy_to_user(argp, mtd, sizeof(struct mtd_info_user)))
+ return -EFAULT;
+ break;
+
+ case MEMERASE:
+ {
+ struct erase_info *erase;
+
+ if(!(file->f_mode & 2))
+ return -EPERM;
+
+ erase=kmalloc(sizeof(struct erase_info),GFP_KERNEL);
+ if (!erase)
+ ret = -ENOMEM;
+ else {
+ wait_queue_head_t waitq;
+ DECLARE_WAITQUEUE(wait, current);
+
+ init_waitqueue_head(&waitq);
+
+ memset (erase,0,sizeof(struct erase_info));
+ if (copy_from_user(&erase->addr, argp,
+ sizeof(struct erase_info_user))) {
+ kfree(erase);
+ return -EFAULT;
+ }
+ erase->mtd = mtd;
+ erase->callback = mtdchar_erase_callback;
+ erase->priv = (unsigned long)&waitq;
+
+ /*
+ FIXME: Allow INTERRUPTIBLE. Which means
+ not having the wait_queue head on the stack.
+
+ If the wq_head is on the stack, and we
+ leave because we got interrupted, then the
+ wq_head is no longer there when the
+ callback routine tries to wake us up.
+ */
+ ret = mtd->erase(mtd, erase);
+ if (!ret) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ add_wait_queue(&waitq, &wait);
+ if (erase->state != MTD_ERASE_DONE &&
+ erase->state != MTD_ERASE_FAILED)
+ schedule();
+ remove_wait_queue(&waitq, &wait);
+ set_current_state(TASK_RUNNING);
+
+ ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
+ }
+ kfree(erase);
+ }
+ break;
+ }
+
+ case MEMWRITEOOB:
+ {
+ struct mtd_oob_buf buf;
+ void *databuf;
+ ssize_t retlen;
+
+ if(!(file->f_mode & 2))
+ return -EPERM;
+
+ if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
+ return -EFAULT;
+
+ if (buf.length > 0x4096)
+ return -EINVAL;
+
+ if (!mtd->write_oob)
+ ret = -EOPNOTSUPP;
+ else
+ ret = access_ok(VERIFY_READ, buf.ptr,
+ buf.length) ? 0 : EFAULT;
+
+ if (ret)
+ return ret;
+
+ databuf = kmalloc(buf.length, GFP_KERNEL);
+ if (!databuf)
+ return -ENOMEM;
+
+ if (copy_from_user(databuf, buf.ptr, buf.length)) {
+ kfree(databuf);
+ return -EFAULT;
+ }
+
+ ret = (mtd->write_oob)(mtd, buf.start, buf.length, &retlen, databuf);
+
+ if (copy_to_user(argp + sizeof(uint32_t), &retlen, sizeof(uint32_t)))
+ ret = -EFAULT;
+
+ kfree(databuf);
+ break;
+
+ }
+
+ case MEMREADOOB:
+ {
+ struct mtd_oob_buf buf;
+ void *databuf;
+ ssize_t retlen;
+
+ if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
+ return -EFAULT;
+
+ if (buf.length > 0x4096)
+ return -EINVAL;
+
+ if (!mtd->read_oob)
+ ret = -EOPNOTSUPP;
+ else
+ ret = access_ok(VERIFY_WRITE, buf.ptr,
+ buf.length) ? 0 : -EFAULT;
+
+ if (ret)
+ return ret;
+
+ databuf = kmalloc(buf.length, GFP_KERNEL);
+ if (!databuf)
+ return -ENOMEM;
+
+ ret = (mtd->read_oob)(mtd, buf.start, buf.length, &retlen, databuf);
+
+ if (put_user(retlen, (uint32_t __user *)argp))
+ ret = -EFAULT;
+ else if (retlen && copy_to_user(buf.ptr, databuf, retlen))
+ ret = -EFAULT;
+
+ kfree(databuf);
+ break;
+ }
+
+ case MEMLOCK:
+ {
+ struct erase_info_user info;
+
+ if (copy_from_user(&info, argp, sizeof(info)))
+ return -EFAULT;
+
+ if (!mtd->lock)
+ ret = -EOPNOTSUPP;
+ else
+ ret = mtd->lock(mtd, info.start, info.length);
+ break;
+ }
+
+ case MEMUNLOCK:
+ {
+ struct erase_info_user info;
+
+ if (copy_from_user(&info, argp, sizeof(info)))
+ return -EFAULT;
+
+ if (!mtd->unlock)
+ ret = -EOPNOTSUPP;
+ else
+ ret = mtd->unlock(mtd, info.start, info.length);
+ break;
+ }
+
+ case MEMSETOOBSEL:
+ {
+ if (copy_from_user(&mtd->oobinfo, argp, sizeof(struct nand_oobinfo)))
+ return -EFAULT;
+ break;
+ }
+
+ case MEMGETOOBSEL:
+ {
+ if (copy_to_user(argp, &(mtd->oobinfo), sizeof(struct nand_oobinfo)))
+ return -EFAULT;
+ break;
+ }
+
+ case MEMGETBADBLOCK:
+ {
+ loff_t offs;
+
+ if (copy_from_user(&offs, argp, sizeof(loff_t)))
+ return -EFAULT;
+ if (!mtd->block_isbad)
+ ret = -EOPNOTSUPP;
+ else
+ return mtd->block_isbad(mtd, offs);
+ break;
+ }
+
+ case MEMSETBADBLOCK:
+ {
+ loff_t offs;
+
+ if (copy_from_user(&offs, argp, sizeof(loff_t)))
+ return -EFAULT;
+ if (!mtd->block_markbad)
+ ret = -EOPNOTSUPP;
+ else
+ return mtd->block_markbad(mtd, offs);
+ break;
+ }
+
+ default:
+ ret = -ENOTTY;
+ }
+
+ return ret;
+} /* memory_ioctl */
+
+static struct file_operations mtd_fops = {
+ .owner = THIS_MODULE,
+ .llseek = mtd_lseek,
+ .read = mtd_read,
+ .write = mtd_write,
+ .ioctl = mtd_ioctl,
+ .open = mtd_open,
+ .release = mtd_close,
+};
+
+static int __init init_mtdchar(void)
+{
+ if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
+ printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
+ MTD_CHAR_MAJOR);
+ return -EAGAIN;
+ }
+
+ mtdchar_devfs_init();
+ return 0;
+}
+
+static void __exit cleanup_mtdchar(void)
+{
+ mtdchar_devfs_exit();
+ unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
+}
+
+module_init(init_mtdchar);
+module_exit(cleanup_mtdchar);
+
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
+MODULE_DESCRIPTION("Direct character-device access to MTD devices");
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-13 15:41:41 +0000