2 * $Id: mtdchar.c,v 1.64 2004/08/09 13:59:46 dwmw2 Exp $
4 * Character-device access to raw MTD devices.
8 #include <linux/config.h>
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/mtd/mtd.h>
12 #include <linux/mtd/compatmac.h>
13 #include <linux/slab.h>
14 #include <linux/init.h>
16 #include <asm/uaccess.h>
18 #ifdef CONFIG_DEVFS_FS
19 #include <linux/devfs_fs_kernel.h>
21 static void mtd_notify_add(struct mtd_info* mtd)
26 devfs_mk_cdev(MKDEV(MTD_CHAR_MAJOR, mtd->index*2),
27 S_IFCHR | S_IRUGO | S_IWUGO, "mtd/%d", mtd->index);
29 devfs_mk_cdev(MKDEV(MTD_CHAR_MAJOR, mtd->index*2+1),
30 S_IFCHR | S_IRUGO, "mtd/%dro", mtd->index);
33 static void mtd_notify_remove(struct mtd_info* mtd)
37 devfs_remove("mtd/%d", mtd->index);
38 devfs_remove("mtd/%dro", mtd->index);
41 static struct mtd_notifier notifier = {
42 .add = mtd_notify_add,
43 .remove = mtd_notify_remove,
46 static inline void mtdchar_devfs_init(void)
49 register_mtd_user(¬ifier);
52 static inline void mtdchar_devfs_exit(void)
54 unregister_mtd_user(¬ifier);
58 #define mtdchar_devfs_init() do { } while(0)
59 #define mtdchar_devfs_exit() do { } while(0)
62 static loff_t mtd_lseek (struct file *file, loff_t offset, int orig)
64 struct mtd_info *mtd=(struct mtd_info *)file->private_data;
73 file->f_pos += offset;
77 file->f_pos =mtd->size + offset;
85 else if (file->f_pos >= mtd->size)
86 file->f_pos = mtd->size - 1;
93 static int mtd_open(struct inode *inode, struct file *file)
95 int minor = iminor(inode);
96 int devnum = minor >> 1;
99 DEBUG(MTD_DEBUG_LEVEL0, "MTD_open\n");
101 if (devnum >= MAX_MTD_DEVICES)
104 /* You can't open the RO devices RW */
105 if ((file->f_mode & 2) && (minor & 1))
108 mtd = get_mtd_device(NULL, devnum);
113 if (MTD_ABSENT == mtd->type) {
118 file->private_data = mtd;
120 /* You can't open it RW if it's not a writeable device */
121 if ((file->f_mode & 2) && !(mtd->flags & MTD_WRITEABLE)) {
129 /*====================================================================*/
131 static int mtd_close(struct inode *inode, struct file *file)
133 struct mtd_info *mtd;
135 DEBUG(MTD_DEBUG_LEVEL0, "MTD_close\n");
137 mtd = (struct mtd_info *)file->private_data;
147 /* FIXME: This _really_ needs to die. In 2.5, we should lock the
148 userspace buffer down and use it directly with readv/writev.
150 #define MAX_KMALLOC_SIZE 0x20000
152 static ssize_t mtd_read(struct file *file, char __user *buf, size_t count,loff_t *ppos)
154 struct mtd_info *mtd = (struct mtd_info *)file->private_data;
156 size_t total_retlen=0;
161 DEBUG(MTD_DEBUG_LEVEL0,"MTD_read\n");
163 if (*ppos + count > mtd->size)
164 count = mtd->size - *ppos;
169 /* FIXME: Use kiovec in 2.5 to lock down the user's buffers
170 and pass them directly to the MTD functions */
172 if (count > MAX_KMALLOC_SIZE)
173 len = MAX_KMALLOC_SIZE;
177 kbuf=kmalloc(len,GFP_KERNEL);
181 ret = MTD_READ(mtd, *ppos, len, &retlen, kbuf);
184 if (copy_to_user(buf, kbuf, retlen)) {
189 total_retlen += retlen;
205 static ssize_t mtd_write(struct file *file, const char __user *buf, size_t count,loff_t *ppos)
207 struct mtd_info *mtd = (struct mtd_info *)file->private_data;
210 size_t total_retlen=0;
214 DEBUG(MTD_DEBUG_LEVEL0,"MTD_write\n");
216 if (*ppos == mtd->size)
219 if (*ppos + count > mtd->size)
220 count = mtd->size - *ppos;
226 if (count > MAX_KMALLOC_SIZE)
227 len = MAX_KMALLOC_SIZE;
231 kbuf=kmalloc(len,GFP_KERNEL);
233 printk("kmalloc is null\n");
237 if (copy_from_user(kbuf, buf, len)) {
242 ret = (*(mtd->write))(mtd, *ppos, len, &retlen, kbuf);
245 total_retlen += retlen;
260 /*======================================================================
262 IOCTL calls for getting device parameters.
264 ======================================================================*/
265 static void mtdchar_erase_callback (struct erase_info *instr)
267 wake_up((wait_queue_head_t *)instr->priv);
270 static int mtd_ioctl(struct inode *inode, struct file *file,
271 u_int cmd, u_long arg)
273 struct mtd_info *mtd = (struct mtd_info *)file->private_data;
274 void __user *argp = (void __user *)arg;
278 DEBUG(MTD_DEBUG_LEVEL0, "MTD_ioctl\n");
280 size = (cmd & IOCSIZE_MASK) >> IOCSIZE_SHIFT;
282 ret = verify_area(VERIFY_READ, argp, size);
286 ret = verify_area(VERIFY_WRITE, argp, size);
291 case MEMGETREGIONCOUNT:
292 if (copy_to_user(argp, &(mtd->numeraseregions), sizeof(int)))
296 case MEMGETREGIONINFO:
298 struct region_info_user ur;
300 if (copy_from_user(&ur, argp, sizeof(struct region_info_user)))
303 if (ur.regionindex >= mtd->numeraseregions)
305 if (copy_to_user(argp, &(mtd->eraseregions[ur.regionindex]),
306 sizeof(struct mtd_erase_region_info)))
312 if (copy_to_user(argp, mtd, sizeof(struct mtd_info_user)))
318 struct erase_info *erase;
320 if(!(file->f_mode & 2))
323 erase=kmalloc(sizeof(struct erase_info),GFP_KERNEL);
327 wait_queue_head_t waitq;
328 DECLARE_WAITQUEUE(wait, current);
330 init_waitqueue_head(&waitq);
332 memset (erase,0,sizeof(struct erase_info));
333 if (copy_from_user(&erase->addr, argp,
334 sizeof(struct erase_info_user))) {
339 erase->callback = mtdchar_erase_callback;
340 erase->priv = (unsigned long)&waitq;
343 FIXME: Allow INTERRUPTIBLE. Which means
344 not having the wait_queue head on the stack.
346 If the wq_head is on the stack, and we
347 leave because we got interrupted, then the
348 wq_head is no longer there when the
349 callback routine tries to wake us up.
351 ret = mtd->erase(mtd, erase);
353 set_current_state(TASK_UNINTERRUPTIBLE);
354 add_wait_queue(&waitq, &wait);
355 if (erase->state != MTD_ERASE_DONE &&
356 erase->state != MTD_ERASE_FAILED)
358 remove_wait_queue(&waitq, &wait);
359 set_current_state(TASK_RUNNING);
361 ret = (erase->state == MTD_ERASE_FAILED)?-EIO:0;
370 struct mtd_oob_buf buf;
374 if(!(file->f_mode & 2))
377 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
380 if (buf.length > 0x4096)
386 ret = verify_area(VERIFY_READ, buf.ptr, buf.length);
391 databuf = kmalloc(buf.length, GFP_KERNEL);
395 if (copy_from_user(databuf, buf.ptr, buf.length)) {
400 ret = (mtd->write_oob)(mtd, buf.start, buf.length, &retlen, databuf);
402 if (copy_to_user(argp + sizeof(uint32_t), &retlen, sizeof(uint32_t)))
412 struct mtd_oob_buf buf;
416 if (copy_from_user(&buf, argp, sizeof(struct mtd_oob_buf)))
419 if (buf.length > 0x4096)
425 ret = verify_area(VERIFY_WRITE, buf.ptr, buf.length);
430 databuf = kmalloc(buf.length, GFP_KERNEL);
434 ret = (mtd->read_oob)(mtd, buf.start, buf.length, &retlen, databuf);
436 if (put_user(retlen, (uint32_t __user *)argp))
438 else if (retlen && copy_to_user(buf.ptr, databuf, retlen))
447 struct erase_info_user info;
449 if (copy_from_user(&info, argp, sizeof(info)))
455 ret = mtd->lock(mtd, info.start, info.length);
461 struct erase_info_user info;
463 if (copy_from_user(&info, argp, sizeof(info)))
469 ret = mtd->unlock(mtd, info.start, info.length);
475 if (copy_from_user(&mtd->oobinfo, argp, sizeof(struct nand_oobinfo)))
482 if (copy_to_user(argp, &(mtd->oobinfo), sizeof(struct nand_oobinfo)))
491 if (copy_from_user(&offs, argp, sizeof(loff_t)))
493 if (!mtd->block_isbad)
496 return mtd->block_isbad(mtd, offs);
504 if (copy_from_user(&offs, argp, sizeof(loff_t)))
506 if (!mtd->block_markbad)
509 return mtd->block_markbad(mtd, offs);
520 static struct file_operations mtd_fops = {
521 .owner = THIS_MODULE,
527 .release = mtd_close,
530 static int __init init_mtdchar(void)
532 if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops)) {
533 printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
538 mtdchar_devfs_init();
542 static void __exit cleanup_mtdchar(void)
544 mtdchar_devfs_exit();
545 unregister_chrdev(MTD_CHAR_MAJOR, "mtd");
548 module_init(init_mtdchar);
549 module_exit(cleanup_mtdchar);
552 MODULE_LICENSE("GPL");
553 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
554 MODULE_DESCRIPTION("Direct character-device access to MTD devices");