/*
   * Simple MTD partitioning layer
   *
   * Copyright © 2000 Nicolas Pitre <nico@fluxnic.net>
   * Copyright © 2002 Thomas Gleixner <gleixner@linutronix.de>
   * Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org>
   *
   * SPDX-License-Identifier:	GPL-2.0+
   *
   */
  
  #ifndef __UBOOT__
  #include <linux/module.h>
  #include <linux/types.h>
  #include <linux/kernel.h>
  #include <linux/slab.h>
  #include <linux/list.h>
  #include <linux/kmod.h>
  #endif
  
  #include <common.h>
  #include <malloc.h>
  #include <asm/errno.h>
  #include <linux/compat.h>
  #include <ubi_uboot.h>
  
  #include <linux/mtd/mtd.h>
  #include <linux/mtd/partitions.h>
  #include <linux/err.h>
  
  #include "mtdcore.h"
  
  /* Our partition linked list */
  static LIST_HEAD(mtd_partitions);
  #ifndef __UBOOT__
  static DEFINE_MUTEX(mtd_partitions_mutex);
  #else
  DEFINE_MUTEX(mtd_partitions_mutex);
  #endif
  
  /* Our partition node structure */
  struct mtd_part {
  	struct mtd_info mtd;
  	struct mtd_info *master;
  	uint64_t offset;
  	struct list_head list;
  };
  
  /*
   * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
   * the pointer to that structure with this macro.
   */
  #define PART(x)  ((struct mtd_part *)(x))
  
  
  #ifdef __UBOOT__
  /* from mm/util.c */
  
  /**
   * kstrdup - allocate space for and copy an existing string
   * @s: the string to duplicate
   * @gfp: the GFP mask used in the kmalloc() call when allocating memory
   */
  char *kstrdup(const char *s, gfp_t gfp)
  {
  	size_t len;
  	char *buf;
  
  	if (!s)
  		return NULL;
  
  	len = strlen(s) + 1;
  	buf = kmalloc(len, gfp);
  	if (buf)
  		memcpy(buf, s, len);
  	return buf;
  }
  #endif
  
  /*
   * MTD methods which simply translate the effective address and pass through
   * to the _real_ device.
   */
  
  static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
  		size_t *retlen, u_char *buf)
  {
  	struct mtd_part *part = PART(mtd);
  	struct mtd_ecc_stats stats;
  	int res;
  
  	stats = part->master->ecc_stats;
  	res = part->master->_read(part->master, from + part->offset, len,
  				  retlen, buf);
  	if (unlikely(mtd_is_eccerr(res)))
  		mtd->ecc_stats.failed +=
  			part->master->ecc_stats.failed - stats.failed;
  	else
  		mtd->ecc_stats.corrected +=
  			part->master->ecc_stats.corrected - stats.corrected;
  	return res;
  }
  
  #ifndef __UBOOT__
  static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
  		size_t *retlen, void **virt, resource_size_t *phys)
  {
  	struct mtd_part *part = PART(mtd);
  
  	return part->master->_point(part->master, from + part->offset, len,
  				    retlen, virt, phys);
  }
  
  static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
  {
  	struct mtd_part *part = PART(mtd);
  
  	return part->master->_unpoint(part->master, from + part->offset, len);
  }
  #endif
  
  static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
  					    unsigned long len,
  					    unsigned long offset,
  					    unsigned long flags)
  {
  	struct mtd_part *part = PART(mtd);
  
  	offset += part->offset;
  	return part->master->_get_unmapped_area(part->master, len, offset,
  						flags);
  }
  
  static int part_read_oob(struct mtd_info *mtd, loff_t from,
  		struct mtd_oob_ops *ops)
  {
  	struct mtd_part *part = PART(mtd);
  	int res;
  
  	if (from >= mtd->size)
  		return -EINVAL;
  	if (ops->datbuf && from + ops->len > mtd->size)
  		return -EINVAL;
  
  	/*
  	 * If OOB is also requested, make sure that we do not read past the end
  	 * of this partition.
  	 */
  	if (ops->oobbuf) {
  		size_t len, pages;
  
  		if (ops->mode == MTD_OPS_AUTO_OOB)
  			len = mtd->oobavail;
  		else
  			len = mtd->oobsize;
  		pages = mtd_div_by_ws(mtd->size, mtd);
  		pages -= mtd_div_by_ws(from, mtd);
  		if (ops->ooboffs + ops->ooblen > pages * len)
  			return -EINVAL;
  	}
  
  	res = part->master->_read_oob(part->master, from + part->offset, ops);
  	if (unlikely(res)) {
  		if (mtd_is_bitflip(res))
  			mtd->ecc_stats.corrected++;
  		if (mtd_is_eccerr(res))
  			mtd->ecc_stats.failed++;
  	}
  	return res;
  }
  
  static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
  		size_t len, size_t *retlen, u_char *buf)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_read_user_prot_reg(part->master, from, len,
  						 retlen, buf);
  }
  
  static int part_get_user_prot_info(struct mtd_info *mtd, size_t len,
  				   size_t *retlen, struct otp_info *buf)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_get_user_prot_info(part->master, len, retlen,
  						 buf);
  }
  
  static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
  		size_t len, size_t *retlen, u_char *buf)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_read_fact_prot_reg(part->master, from, len,
  						 retlen, buf);
  }
  
  static int part_get_fact_prot_info(struct mtd_info *mtd, size_t len,
  				   size_t *retlen, struct otp_info *buf)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_get_fact_prot_info(part->master, len, retlen,
  						 buf);
  }
  
  static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
  		size_t *retlen, const u_char *buf)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_write(part->master, to + part->offset, len,
  				    retlen, buf);
  }
  
  static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
  		size_t *retlen, const u_char *buf)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_panic_write(part->master, to + part->offset, len,
  					  retlen, buf);
  }
  
  static int part_write_oob(struct mtd_info *mtd, loff_t to,
  		struct mtd_oob_ops *ops)
  {
  	struct mtd_part *part = PART(mtd);
  
  	if (to >= mtd->size)
  		return -EINVAL;
  	if (ops->datbuf && to + ops->len > mtd->size)
  		return -EINVAL;
  	return part->master->_write_oob(part->master, to + part->offset, ops);
  }
  
  static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
  		size_t len, size_t *retlen, u_char *buf)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_write_user_prot_reg(part->master, from, len,
  						  retlen, buf);
  }
  
  static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
  		size_t len)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_lock_user_prot_reg(part->master, from, len);
  }
  
  #ifndef __UBOOT__
  static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
  		unsigned long count, loff_t to, size_t *retlen)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_writev(part->master, vecs, count,
  				     to + part->offset, retlen);
  }
  #endif
  
  static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
  {
  	struct mtd_part *part = PART(mtd);
  	int ret;
  
  	instr->addr += part->offset;
  	ret = part->master->_erase(part->master, instr);
  	if (ret) {
  		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
  			instr->fail_addr -= part->offset;
  		instr->addr -= part->offset;
  	}
  	return ret;
  }
  
  void mtd_erase_callback(struct erase_info *instr)
  {
  	if (instr->mtd->_erase == part_erase) {
  		struct mtd_part *part = PART(instr->mtd);
  
  		if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
  			instr->fail_addr -= part->offset;
  		instr->addr -= part->offset;
  	}
  	if (instr->callback)
  		instr->callback(instr);
  }
  EXPORT_SYMBOL_GPL(mtd_erase_callback);
  
  static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_lock(part->master, ofs + part->offset, len);
  }
  
  static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_unlock(part->master, ofs + part->offset, len);
  }
  
  static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_is_locked(part->master, ofs + part->offset, len);
  }
  
  static void part_sync(struct mtd_info *mtd)
  {
  	struct mtd_part *part = PART(mtd);
  	part->master->_sync(part->master);
  }
  
  #ifndef __UBOOT__
  static int part_suspend(struct mtd_info *mtd)
  {
  	struct mtd_part *part = PART(mtd);
  	return part->master->_suspend(part->master);
  }
  
  static void part_resume(struct mtd_info *mtd)
  {
  	struct mtd_part *part = PART(mtd);
  	part->master->_resume(part->master);
  }
  #endif
  
  static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
  {
  	struct mtd_part *part = PART(mtd);
  	ofs += part->offset;
  	return part->master->_block_isbad(part->master, ofs);
  }
  
  static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
  {
  	struct mtd_part *part = PART(mtd);
  	int res;
  
  	ofs += part->offset;
  	res = part->master->_block_markbad(part->master, ofs);
  	if (!res)
  		mtd->ecc_stats.badblocks++;
  	return res;
  }
  
  static inline void free_partition(struct mtd_part *p)
  {
  	kfree(p->mtd.name);
  	kfree(p);
  }
  
  /*
   * This function unregisters and destroy all slave MTD objects which are
   * attached to the given master MTD object.
   */
  
  int del_mtd_partitions(struct mtd_info *master)
  {
  	struct mtd_part *slave, *next;
  	int ret, err = 0;
  
  	mutex_lock(&mtd_partitions_mutex);
  	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
  		if (slave->master == master) {
  			ret = del_mtd_device(&slave->mtd);
  			if (ret < 0) {
  				err = ret;
  				continue;
  			}
  			list_del(&slave->list);
  			free_partition(slave);
  		}
  	mutex_unlock(&mtd_partitions_mutex);
  
  	return err;
  }
  
  static struct mtd_part *allocate_partition(struct mtd_info *master,
  			const struct mtd_partition *part, int partno,
  			uint64_t cur_offset)
  {
  	struct mtd_part *slave;
  	char *name;
  
  	/* allocate the partition structure */
  	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
  	name = kstrdup(part->name, GFP_KERNEL);
  	if (!name || !slave) {
  		printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"
  ",
  		       master->name);
  		kfree(name);
  		kfree(slave);
  		return ERR_PTR(-ENOMEM);
  	}
  
  	/* set up the MTD object for this partition */
  	slave->mtd.type = master->type;
  	slave->mtd.flags = master->flags & ~part->mask_flags;
  	slave->mtd.size = part->size;
  	slave->mtd.writesize = master->writesize;
  	slave->mtd.writebufsize = master->writebufsize;
  	slave->mtd.oobsize = master->oobsize;
  	slave->mtd.oobavail = master->oobavail;
  	slave->mtd.subpage_sft = master->subpage_sft;
  
  	slave->mtd.name = name;
  	slave->mtd.owner = master->owner;
  #ifndef __UBOOT__
  	slave->mtd.backing_dev_info = master->backing_dev_info;
  
  	/* NOTE:  we don't arrange MTDs as a tree; it'd be error-prone
  	 * to have the same data be in two different partitions.
  	 */
  	slave->mtd.dev.parent = master->dev.parent;
  #endif
  
  	slave->mtd._read = part_read;
  	slave->mtd._write = part_write;
  
  	if (master->_panic_write)
  		slave->mtd._panic_write = part_panic_write;
  
  #ifndef __UBOOT__
  	if (master->_point && master->_unpoint) {
  		slave->mtd._point = part_point;
  		slave->mtd._unpoint = part_unpoint;
  	}
  #endif
  
  	if (master->_get_unmapped_area)
  		slave->mtd._get_unmapped_area = part_get_unmapped_area;
  	if (master->_read_oob)
  		slave->mtd._read_oob = part_read_oob;
  	if (master->_write_oob)
  		slave->mtd._write_oob = part_write_oob;
  	if (master->_read_user_prot_reg)
  		slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
  	if (master->_read_fact_prot_reg)
  		slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
  	if (master->_write_user_prot_reg)
  		slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
  	if (master->_lock_user_prot_reg)
  		slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
  	if (master->_get_user_prot_info)
  		slave->mtd._get_user_prot_info = part_get_user_prot_info;
  	if (master->_get_fact_prot_info)
  		slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
  	if (master->_sync)
  		slave->mtd._sync = part_sync;
  #ifndef __UBOOT__
  	if (!partno && !master->dev.class && master->_suspend &&
  	    master->_resume) {
  			slave->mtd._suspend = part_suspend;
  			slave->mtd._resume = part_resume;
  	}
  	if (master->_writev)
  		slave->mtd._writev = part_writev;
  #endif
  	if (master->_lock)
  		slave->mtd._lock = part_lock;
  	if (master->_unlock)
  		slave->mtd._unlock = part_unlock;
  	if (master->_is_locked)
  		slave->mtd._is_locked = part_is_locked;
  	if (master->_block_isbad)
  		slave->mtd._block_isbad = part_block_isbad;
  	if (master->_block_markbad)
  		slave->mtd._block_markbad = part_block_markbad;
  	slave->mtd._erase = part_erase;
  	slave->master = master;
  	slave->offset = part->offset;
  
  	if (slave->offset == MTDPART_OFS_APPEND)
  		slave->offset = cur_offset;
  	if (slave->offset == MTDPART_OFS_NXTBLK) {
  		slave->offset = cur_offset;
  		if (mtd_mod_by_eb(cur_offset, master) != 0) {
  			/* Round up to next erasesize */
  			slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
  			debug("Moving partition %d: "
  			       "0x%012llx -> 0x%012llx
  ", partno,
  			       (unsigned long long)cur_offset, (unsigned long long)slave->offset);
  		}
  	}
  	if (slave->offset == MTDPART_OFS_RETAIN) {
  		slave->offset = cur_offset;
  		if (master->size - slave->offset >= slave->mtd.size) {
  			slave->mtd.size = master->size - slave->offset
  							- slave->mtd.size;
  		} else {
  			debug("mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled
  ",
  				part->name, master->size - slave->offset,
  				slave->mtd.size);
  			/* register to preserve ordering */
  			goto out_register;
  		}
  	}
  	if (slave->mtd.size == MTDPART_SIZ_FULL)
  		slave->mtd.size = master->size - slave->offset;
  
  	debug("0x%012llx-0x%012llx : \"%s\"
  ", (unsigned long long)slave->offset,
  		(unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
  
  	/* let's do some sanity checks */
  	if (slave->offset >= master->size) {
  		/* let's register it anyway to preserve ordering */
  		slave->offset = 0;
  		slave->mtd.size = 0;
  		printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled
  ",
  			part->name);
  		goto out_register;
  	}
  	if (slave->offset + slave->mtd.size > master->size) {
  		slave->mtd.size = master->size - slave->offset;
  		printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx
  ",
  			part->name, master->name, (unsigned long long)slave->mtd.size);
  	}
  	if (master->numeraseregions > 1) {
  		/* Deal with variable erase size stuff */
  		int i, max = master->numeraseregions;
  		u64 end = slave->offset + slave->mtd.size;
  		struct mtd_erase_region_info *regions = master->eraseregions;
  
  		/* Find the first erase regions which is part of this
  		 * partition. */
  		for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
  			;
  		/* The loop searched for the region _behind_ the first one */
  		if (i > 0)
  			i--;
  
  		/* Pick biggest erasesize */
  		for (; i < max && regions[i].offset < end; i++) {
  			if (slave->mtd.erasesize < regions[i].erasesize) {
  				slave->mtd.erasesize = regions[i].erasesize;
  			}
  		}
  		BUG_ON(slave->mtd.erasesize == 0);
  	} else {
  		/* Single erase size */
  		slave->mtd.erasesize = master->erasesize;
  	}
  
  	if ((slave->mtd.flags & MTD_WRITEABLE) &&
  	    mtd_mod_by_eb(slave->offset, &slave->mtd)) {
  		/* Doesn't start on a boundary of major erase size */
  		/* FIXME: Let it be writable if it is on a boundary of
  		 * _minor_ erase size though */
  		slave->mtd.flags &= ~MTD_WRITEABLE;
  		printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only
  ",
  			part->name);
  	}
  	if ((slave->mtd.flags & MTD_WRITEABLE) &&
  	    mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
  		slave->mtd.flags &= ~MTD_WRITEABLE;
  		printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only
  ",
  			part->name);
  	}
  
  	slave->mtd.ecclayout = master->ecclayout;
  	slave->mtd.ecc_step_size = master->ecc_step_size;
  	slave->mtd.ecc_strength = master->ecc_strength;
  	slave->mtd.bitflip_threshold = master->bitflip_threshold;
  
  	if (master->_block_isbad) {
  		uint64_t offs = 0;
  
  		while (offs < slave->mtd.size) {
  			if (mtd_block_isbad(master, offs + slave->offset))
  				slave->mtd.ecc_stats.badblocks++;
  			offs += slave->mtd.erasesize;
  		}
  	}
  
  out_register:
  	return slave;
  }
  
  #ifndef __UBOOT__
  int mtd_add_partition(struct mtd_info *master, const char *name,
  		      long long offset, long long length)
  {
  	struct mtd_partition part;
  	struct mtd_part *p, *new;
  	uint64_t start, end;
  	int ret = 0;
  
  	/* the direct offset is expected */
  	if (offset == MTDPART_OFS_APPEND ||
  	    offset == MTDPART_OFS_NXTBLK)
  		return -EINVAL;
  
  	if (length == MTDPART_SIZ_FULL)
  		length = master->size - offset;
  
  	if (length <= 0)
  		return -EINVAL;
  
  	part.name = name;
  	part.size = length;
  	part.offset = offset;
  	part.mask_flags = 0;
  	part.ecclayout = NULL;
  
  	new = allocate_partition(master, &part, -1, offset);
  	if (IS_ERR(new))
  		return PTR_ERR(new);
  
  	start = offset;
  	end = offset + length;
  
  	mutex_lock(&mtd_partitions_mutex);
  	list_for_each_entry(p, &mtd_partitions, list)
  		if (p->master == master) {
  			if ((start >= p->offset) &&
  			    (start < (p->offset + p->mtd.size)))
  				goto err_inv;
  
  			if ((end >= p->offset) &&
  			    (end < (p->offset + p->mtd.size)))
  				goto err_inv;
  		}
  
  	list_add(&new->list, &mtd_partitions);
  	mutex_unlock(&mtd_partitions_mutex);
  
  	add_mtd_device(&new->mtd);
  
  	return ret;
  err_inv:
  	mutex_unlock(&mtd_partitions_mutex);
  	free_partition(new);
  	return -EINVAL;
  }
  EXPORT_SYMBOL_GPL(mtd_add_partition);
  
  int mtd_del_partition(struct mtd_info *master, int partno)
  {
  	struct mtd_part *slave, *next;
  	int ret = -EINVAL;
  
  	mutex_lock(&mtd_partitions_mutex);
  	list_for_each_entry_safe(slave, next, &mtd_partitions, list)
  		if ((slave->master == master) &&
  		    (slave->mtd.index == partno)) {
  			ret = del_mtd_device(&slave->mtd);
  			if (ret < 0)
  				break;
  
  			list_del(&slave->list);
  			free_partition(slave);
  			break;
  		}
  	mutex_unlock(&mtd_partitions_mutex);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(mtd_del_partition);
  #endif
  
  /*
   * This function, given a master MTD object and a partition table, creates
   * and registers slave MTD objects which are bound to the master according to
   * the partition definitions.
   *
   * We don't register the master, or expect the caller to have done so,
   * for reasons of data integrity.
   */
  
  int add_mtd_partitions(struct mtd_info *master,
  		       const struct mtd_partition *parts,
  		       int nbparts)
  {
  	struct mtd_part *slave;
  	uint64_t cur_offset = 0;
  	int i;
  
  #ifdef __UBOOT__
  	/*
  	 * Need to init the list here, since LIST_INIT() does not
  	 * work on platforms where relocation has problems (like MIPS
  	 * & PPC).
  	 */
  	if (mtd_partitions.next == NULL)
  		INIT_LIST_HEAD(&mtd_partitions);
  #endif
  
  	debug("Creating %d MTD partitions on \"%s\":
  ", nbparts, master->name);
  
  	for (i = 0; i < nbparts; i++) {
  		slave = allocate_partition(master, parts + i, i, cur_offset);
  		if (IS_ERR(slave))
  			return PTR_ERR(slave);
  
  		mutex_lock(&mtd_partitions_mutex);
  		list_add(&slave->list, &mtd_partitions);
  		mutex_unlock(&mtd_partitions_mutex);
  
  		add_mtd_device(&slave->mtd);
  
  		cur_offset = slave->offset + slave->mtd.size;
  	}
  
  	return 0;
  }
  
  #ifndef __UBOOT__
  static DEFINE_SPINLOCK(part_parser_lock);
  static LIST_HEAD(part_parsers);
  
  static struct mtd_part_parser *get_partition_parser(const char *name)
  {
  	struct mtd_part_parser *p, *ret = NULL;
  
  	spin_lock(&part_parser_lock);
  
  	list_for_each_entry(p, &part_parsers, list)
  		if (!strcmp(p->name, name) && try_module_get(p->owner)) {
  			ret = p;
  			break;
  		}
  
  	spin_unlock(&part_parser_lock);
  
  	return ret;
  }
  
  #define put_partition_parser(p) do { module_put((p)->owner); } while (0)
  
  void register_mtd_parser(struct mtd_part_parser *p)
  {
  	spin_lock(&part_parser_lock);
  	list_add(&p->list, &part_parsers);
  	spin_unlock(&part_parser_lock);
  }
  EXPORT_SYMBOL_GPL(register_mtd_parser);
  
  void deregister_mtd_parser(struct mtd_part_parser *p)
  {
  	spin_lock(&part_parser_lock);
  	list_del(&p->list);
  	spin_unlock(&part_parser_lock);
  }
  EXPORT_SYMBOL_GPL(deregister_mtd_parser);
  
  /*
   * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
   * are changing this array!
   */
  static const char * const default_mtd_part_types[] = {
  	"cmdlinepart",
  	"ofpart",
  	NULL
  };
  
  /**
   * parse_mtd_partitions - parse MTD partitions
   * @master: the master partition (describes whole MTD device)
   * @types: names of partition parsers to try or %NULL
   * @pparts: array of partitions found is returned here
   * @data: MTD partition parser-specific data
   *
   * This function tries to find partition on MTD device @master. It uses MTD
   * partition parsers, specified in @types. However, if @types is %NULL, then
   * the default list of parsers is used. The default list contains only the
   * "cmdlinepart" and "ofpart" parsers ATM.
   * Note: If there are more then one parser in @types, the kernel only takes the
   * partitions parsed out by the first parser.
   *
   * This function may return:
   * o a negative error code in case of failure
   * o zero if no partitions were found
   * o a positive number of found partitions, in which case on exit @pparts will
   *   point to an array containing this number of &struct mtd_info objects.
   */
  int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
  			 struct mtd_partition **pparts,
  			 struct mtd_part_parser_data *data)
  {
  	struct mtd_part_parser *parser;
  	int ret = 0;
  
  	if (!types)
  		types = default_mtd_part_types;
  
  	for ( ; ret <= 0 && *types; types++) {
  		parser = get_partition_parser(*types);
  		if (!parser && !request_module("%s", *types))
  			parser = get_partition_parser(*types);
  		if (!parser)
  			continue;
  		ret = (*parser->parse_fn)(master, pparts, data);
  		put_partition_parser(parser);
  		if (ret > 0) {
  			printk(KERN_NOTICE "%d %s partitions found on MTD device %s
  ",
  			       ret, parser->name, master->name);
  			break;
  		}
  	}
  	return ret;
  }
  #endif
  
  int mtd_is_partition(const struct mtd_info *mtd)
  {
  	struct mtd_part *part;
  	int ispart = 0;
  
  	mutex_lock(&mtd_partitions_mutex);
  	list_for_each_entry(part, &mtd_partitions, list)
  		if (&part->mtd == mtd) {
  			ispart = 1;
  			break;
  		}
  	mutex_unlock(&mtd_partitions_mutex);
  
  	return ispart;
  }
  EXPORT_SYMBOL_GPL(mtd_is_partition);
  
  /* Returns the size of the entire flash chip */
  uint64_t mtd_get_device_size(const struct mtd_info *mtd)
  {
  	if (!mtd_is_partition(mtd))
  		return mtd->size;
  
  	return PART(mtd)->master->size;
  }
  EXPORT_SYMBOL_GPL(mtd_get_device_size);