/* * $Id: mtdchar.c,v 1.66 2005/01/05 18:05:11 dwmw2 Exp $ * * Character-device access to raw MTD devices. * */ #include #include #include #include #include #include #include #include #include #ifdef CONFIG_DEVFS_FS #include 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(¬ifier); } static inline void mtdchar_devfs_exit(void) { unregister_mtd_user(¬ifier); 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 "); MODULE_DESCRIPTION("Direct character-device access to MTD devices");