diff options
Diffstat (limited to 'drivers/mtd/mtdpart.c')
| -rw-r--r-- | drivers/mtd/mtdpart.c | 1055 |
1 files changed, 1055 insertions, 0 deletions
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c new file mode 100644 index 000000000..10c53364a --- /dev/null +++ b/drivers/mtd/mtdpart.c @@ -0,0 +1,1055 @@ +/* + * 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> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/list.h> +#include <linux/kmod.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/partitions.h> +#include <linux/err.h> +#include <linux/of.h> + +#include "mtdcore.h" + +/* Our partition linked list */ +static LIST_HEAD(mtd_partitions); +static DEFINE_MUTEX(mtd_partitions_mutex); + +/** + * struct mtd_part - our partition node structure + * + * @mtd: struct holding partition details + * @parent: parent mtd - flash device or another partition + * @offset: partition offset relative to the *flash device* + */ +struct mtd_part { + struct mtd_info mtd; + struct mtd_info *parent; + 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. + */ +static inline struct mtd_part *mtd_to_part(const struct mtd_info *mtd) +{ + return container_of(mtd, struct mtd_part, mtd); +} + + +/* + * 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 = mtd_to_part(mtd); + struct mtd_ecc_stats stats; + int res; + + stats = part->parent->ecc_stats; + res = part->parent->_read(part->parent, from + part->offset, len, + retlen, buf); + if (unlikely(mtd_is_eccerr(res))) + mtd->ecc_stats.failed += + part->parent->ecc_stats.failed - stats.failed; + else + mtd->ecc_stats.corrected += + part->parent->ecc_stats.corrected - stats.corrected; + return res; +} + +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 = mtd_to_part(mtd); + + return part->parent->_point(part->parent, 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 = mtd_to_part(mtd); + + return part->parent->_unpoint(part->parent, from + part->offset, len); +} + +static int part_read_oob(struct mtd_info *mtd, loff_t from, + struct mtd_oob_ops *ops) +{ + struct mtd_part *part = mtd_to_part(mtd); + struct mtd_ecc_stats stats; + int res; + + stats = part->parent->ecc_stats; + res = part->parent->_read_oob(part->parent, from + part->offset, ops); + if (unlikely(mtd_is_eccerr(res))) + mtd->ecc_stats.failed += + part->parent->ecc_stats.failed - stats.failed; + else + mtd->ecc_stats.corrected += + part->parent->ecc_stats.corrected - stats.corrected; + 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 = mtd_to_part(mtd); + return part->parent->_read_user_prot_reg(part->parent, 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 = mtd_to_part(mtd); + return part->parent->_get_user_prot_info(part->parent, 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 = mtd_to_part(mtd); + return part->parent->_read_fact_prot_reg(part->parent, 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 = mtd_to_part(mtd); + return part->parent->_get_fact_prot_info(part->parent, 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 = mtd_to_part(mtd); + return part->parent->_write(part->parent, 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 = mtd_to_part(mtd); + return part->parent->_panic_write(part->parent, 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 = mtd_to_part(mtd); + + return part->parent->_write_oob(part->parent, 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 = mtd_to_part(mtd); + return part->parent->_write_user_prot_reg(part->parent, 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 = mtd_to_part(mtd); + return part->parent->_lock_user_prot_reg(part->parent, from, len); +} + +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 = mtd_to_part(mtd); + return part->parent->_writev(part->parent, vecs, count, + to + part->offset, retlen); +} + +static int part_erase(struct mtd_info *mtd, struct erase_info *instr) +{ + struct mtd_part *part = mtd_to_part(mtd); + int ret; + + instr->addr += part->offset; + ret = part->parent->_erase(part->parent, instr); + if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN) + instr->fail_addr -= part->offset; + instr->addr -= part->offset; + + return ret; +} + +static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len) +{ + struct mtd_part *part = mtd_to_part(mtd); + return part->parent->_lock(part->parent, ofs + part->offset, len); +} + +static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len) +{ + struct mtd_part *part = mtd_to_part(mtd); + return part->parent->_unlock(part->parent, ofs + part->offset, len); +} + +static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len) +{ + struct mtd_part *part = mtd_to_part(mtd); + return part->parent->_is_locked(part->parent, ofs + part->offset, len); +} + +static void part_sync(struct mtd_info *mtd) +{ + struct mtd_part *part = mtd_to_part(mtd); + part->parent->_sync(part->parent); +} + +static int part_suspend(struct mtd_info *mtd) +{ + struct mtd_part *part = mtd_to_part(mtd); + return part->parent->_suspend(part->parent); +} + +static void part_resume(struct mtd_info *mtd) +{ + struct mtd_part *part = mtd_to_part(mtd); + part->parent->_resume(part->parent); +} + +static int part_block_isreserved(struct mtd_info *mtd, loff_t ofs) +{ + struct mtd_part *part = mtd_to_part(mtd); + ofs += part->offset; + return part->parent->_block_isreserved(part->parent, ofs); +} + +static int part_block_isbad(struct mtd_info *mtd, loff_t ofs) +{ + struct mtd_part *part = mtd_to_part(mtd); + ofs += part->offset; + return part->parent->_block_isbad(part->parent, ofs); +} + +static int part_block_markbad(struct mtd_info *mtd, loff_t ofs) +{ + struct mtd_part *part = mtd_to_part(mtd); + int res; + + ofs += part->offset; + res = part->parent->_block_markbad(part->parent, ofs); + if (!res) + mtd->ecc_stats.badblocks++; + return res; +} + +static int part_get_device(struct mtd_info *mtd) +{ + struct mtd_part *part = mtd_to_part(mtd); + return part->parent->_get_device(part->parent); +} + +static void part_put_device(struct mtd_info *mtd) +{ + struct mtd_part *part = mtd_to_part(mtd); + part->parent->_put_device(part->parent); +} + +static int part_ooblayout_ecc(struct mtd_info *mtd, int section, + struct mtd_oob_region *oobregion) +{ + struct mtd_part *part = mtd_to_part(mtd); + + return mtd_ooblayout_ecc(part->parent, section, oobregion); +} + +static int part_ooblayout_free(struct mtd_info *mtd, int section, + struct mtd_oob_region *oobregion) +{ + struct mtd_part *part = mtd_to_part(mtd); + + return mtd_ooblayout_free(part->parent, section, oobregion); +} + +static const struct mtd_ooblayout_ops part_ooblayout_ops = { + .ecc = part_ooblayout_ecc, + .free = part_ooblayout_free, +}; + +static int part_max_bad_blocks(struct mtd_info *mtd, loff_t ofs, size_t len) +{ + struct mtd_part *part = mtd_to_part(mtd); + + return part->parent->_max_bad_blocks(part->parent, + ofs + part->offset, len); +} + +static inline void free_partition(struct mtd_part *p) +{ + kfree(p->mtd.name); + kfree(p); +} + +static struct mtd_part *allocate_partition(struct mtd_info *parent, + const struct mtd_partition *part, int partno, + uint64_t cur_offset) +{ + int wr_alignment = (parent->flags & MTD_NO_ERASE) ? parent->writesize : + parent->erasesize; + struct mtd_part *slave; + u32 remainder; + char *name; + u64 tmp; + + /* 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\"\n", + parent->name); + kfree(name); + kfree(slave); + return ERR_PTR(-ENOMEM); + } + + /* set up the MTD object for this partition */ + slave->mtd.type = parent->type; + slave->mtd.flags = parent->flags & ~part->mask_flags; + slave->mtd.size = part->size; + slave->mtd.writesize = parent->writesize; + slave->mtd.writebufsize = parent->writebufsize; + slave->mtd.oobsize = parent->oobsize; + slave->mtd.oobavail = parent->oobavail; + slave->mtd.subpage_sft = parent->subpage_sft; + slave->mtd.pairing = parent->pairing; + + slave->mtd.name = name; + slave->mtd.owner = parent->owner; + + /* NOTE: Historically, we didn't arrange MTDs as a tree out of + * concern for showing the same data in multiple partitions. + * However, it is very useful to have the master node present, + * so the MTD_PARTITIONED_MASTER option allows that. The master + * will have device nodes etc only if this is set, so make the + * parent conditional on that option. Note, this is a way to + * distinguish between the master and the partition in sysfs. + */ + slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) || mtd_is_partition(parent) ? + &parent->dev : + parent->dev.parent; + slave->mtd.dev.of_node = part->of_node; + + if (parent->_read) + slave->mtd._read = part_read; + if (parent->_write) + slave->mtd._write = part_write; + + if (parent->_panic_write) + slave->mtd._panic_write = part_panic_write; + + if (parent->_point && parent->_unpoint) { + slave->mtd._point = part_point; + slave->mtd._unpoint = part_unpoint; + } + + if (parent->_read_oob) + slave->mtd._read_oob = part_read_oob; + if (parent->_write_oob) + slave->mtd._write_oob = part_write_oob; + if (parent->_read_user_prot_reg) + slave->mtd._read_user_prot_reg = part_read_user_prot_reg; + if (parent->_read_fact_prot_reg) + slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg; + if (parent->_write_user_prot_reg) + slave->mtd._write_user_prot_reg = part_write_user_prot_reg; + if (parent->_lock_user_prot_reg) + slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg; + if (parent->_get_user_prot_info) + slave->mtd._get_user_prot_info = part_get_user_prot_info; + if (parent->_get_fact_prot_info) + slave->mtd._get_fact_prot_info = part_get_fact_prot_info; + if (parent->_sync) + slave->mtd._sync = part_sync; + if (!partno && !parent->dev.class && parent->_suspend && + parent->_resume) { + slave->mtd._suspend = part_suspend; + slave->mtd._resume = part_resume; + } + if (parent->_writev) + slave->mtd._writev = part_writev; + if (parent->_lock) + slave->mtd._lock = part_lock; + if (parent->_unlock) + slave->mtd._unlock = part_unlock; + if (parent->_is_locked) + slave->mtd._is_locked = part_is_locked; + if (parent->_block_isreserved) + slave->mtd._block_isreserved = part_block_isreserved; + if (parent->_block_isbad) + slave->mtd._block_isbad = part_block_isbad; + if (parent->_block_markbad) + slave->mtd._block_markbad = part_block_markbad; + if (parent->_max_bad_blocks) + slave->mtd._max_bad_blocks = part_max_bad_blocks; + + if (parent->_get_device) + slave->mtd._get_device = part_get_device; + if (parent->_put_device) + slave->mtd._put_device = part_put_device; + + slave->mtd._erase = part_erase; + slave->parent = parent; + slave->offset = part->offset; + + if (slave->offset == MTDPART_OFS_APPEND) + slave->offset = cur_offset; + if (slave->offset == MTDPART_OFS_NXTBLK) { + tmp = cur_offset; + slave->offset = cur_offset; + remainder = do_div(tmp, wr_alignment); + if (remainder) { + slave->offset += wr_alignment - remainder; + printk(KERN_NOTICE "Moving partition %d: " + "0x%012llx -> 0x%012llx\n", partno, + (unsigned long long)cur_offset, (unsigned long long)slave->offset); + } + } + if (slave->offset == MTDPART_OFS_RETAIN) { + slave->offset = cur_offset; + if (parent->size - slave->offset >= slave->mtd.size) { + slave->mtd.size = parent->size - slave->offset + - slave->mtd.size; + } else { + printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n", + part->name, parent->size - slave->offset, + slave->mtd.size); + /* register to preserve ordering */ + goto out_register; + } + } + if (slave->mtd.size == MTDPART_SIZ_FULL) + slave->mtd.size = parent->size - slave->offset; + + printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (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 >= parent->size) { + /* let's register it anyway to preserve ordering */ + slave->offset = 0; + slave->mtd.size = 0; + + /* Initialize ->erasesize to make add_mtd_device() happy. */ + slave->mtd.erasesize = parent->erasesize; + + printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n", + part->name); + goto out_register; + } + if (slave->offset + slave->mtd.size > parent->size) { + slave->mtd.size = parent->size - slave->offset; + printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n", + part->name, parent->name, (unsigned long long)slave->mtd.size); + } + if (parent->numeraseregions > 1) { + /* Deal with variable erase size stuff */ + int i, max = parent->numeraseregions; + u64 end = slave->offset + slave->mtd.size; + struct mtd_erase_region_info *regions = parent->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 = parent->erasesize; + } + + /* + * Slave erasesize might differ from the master one if the master + * exposes several regions with different erasesize. Adjust + * wr_alignment accordingly. + */ + if (!(slave->mtd.flags & MTD_NO_ERASE)) + wr_alignment = slave->mtd.erasesize; + + tmp = slave->offset; + remainder = do_div(tmp, wr_alignment); + if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) { + /* 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/write block boundary -- force read-only\n", + part->name); + } + + tmp = slave->mtd.size; + remainder = do_div(tmp, wr_alignment); + if ((slave->mtd.flags & MTD_WRITEABLE) && remainder) { + slave->mtd.flags &= ~MTD_WRITEABLE; + printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase/write block -- force read-only\n", + part->name); + } + + mtd_set_ooblayout(&slave->mtd, &part_ooblayout_ops); + slave->mtd.ecc_step_size = parent->ecc_step_size; + slave->mtd.ecc_strength = parent->ecc_strength; + slave->mtd.bitflip_threshold = parent->bitflip_threshold; + + if (parent->_block_isbad) { + uint64_t offs = 0; + + while (offs < slave->mtd.size) { + if (mtd_block_isreserved(parent, offs + slave->offset)) + slave->mtd.ecc_stats.bbtblocks++; + else if (mtd_block_isbad(parent, offs + slave->offset)) + slave->mtd.ecc_stats.badblocks++; + offs += slave->mtd.erasesize; + } + } + +out_register: + return slave; +} + +static ssize_t mtd_partition_offset_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct mtd_info *mtd = dev_get_drvdata(dev); + struct mtd_part *part = mtd_to_part(mtd); + return snprintf(buf, PAGE_SIZE, "%lld\n", part->offset); +} + +static DEVICE_ATTR(offset, S_IRUGO, mtd_partition_offset_show, NULL); + +static const struct attribute *mtd_partition_attrs[] = { + &dev_attr_offset.attr, + NULL +}; + +static int mtd_add_partition_attrs(struct mtd_part *new) +{ + int ret = sysfs_create_files(&new->mtd.dev.kobj, mtd_partition_attrs); + if (ret) + printk(KERN_WARNING + "mtd: failed to create partition attrs, err=%d\n", ret); + return ret; +} + +int mtd_add_partition(struct mtd_info *parent, const char *name, + long long offset, long long length) +{ + struct mtd_partition part; + struct mtd_part *new; + 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 = parent->size - offset; + + if (length <= 0) + return -EINVAL; + + memset(&part, 0, sizeof(part)); + part.name = name; + part.size = length; + part.offset = offset; + + new = allocate_partition(parent, &part, -1, offset); + if (IS_ERR(new)) + return PTR_ERR(new); + + mutex_lock(&mtd_partitions_mutex); + list_add(&new->list, &mtd_partitions); + mutex_unlock(&mtd_partitions_mutex); + + ret = add_mtd_device(&new->mtd); + if (ret) + goto err_remove_part; + + mtd_add_partition_attrs(new); + + return 0; + +err_remove_part: + mutex_lock(&mtd_partitions_mutex); + list_del(&new->list); + mutex_unlock(&mtd_partitions_mutex); + + free_partition(new); + + return ret; +} +EXPORT_SYMBOL_GPL(mtd_add_partition); + +/** + * __mtd_del_partition - delete MTD partition + * + * @priv: internal MTD struct for partition to be deleted + * + * This function must be called with the partitions mutex locked. + */ +static int __mtd_del_partition(struct mtd_part *priv) +{ + struct mtd_part *child, *next; + int err; + + list_for_each_entry_safe(child, next, &mtd_partitions, list) { + if (child->parent == &priv->mtd) { + err = __mtd_del_partition(child); + if (err) + return err; + } + } + + sysfs_remove_files(&priv->mtd.dev.kobj, mtd_partition_attrs); + + err = del_mtd_device(&priv->mtd); + if (err) + return err; + + list_del(&priv->list); + free_partition(priv); + + return 0; +} + +/* + * This function unregisters and destroy all slave MTD objects which are + * attached to the given MTD object. + */ +int del_mtd_partitions(struct mtd_info *mtd) +{ + 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->parent == mtd) { + ret = __mtd_del_partition(slave); + if (ret < 0) + err = ret; + } + mutex_unlock(&mtd_partitions_mutex); + + return err; +} + +int mtd_del_partition(struct mtd_info *mtd, 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->parent == mtd) && + (slave->mtd.index == partno)) { + ret = __mtd_del_partition(slave); + break; + } + mutex_unlock(&mtd_partitions_mutex); + + return ret; +} +EXPORT_SYMBOL_GPL(mtd_del_partition); + +/* + * 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. + * + * For historical reasons, this function's caller only registers the master + * if the MTD_PARTITIONED_MASTER config option is set. + */ + +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, ret; + + printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name); + + for (i = 0; i < nbparts; i++) { + slave = allocate_partition(master, parts + i, i, cur_offset); + if (IS_ERR(slave)) { + ret = PTR_ERR(slave); + goto err_del_partitions; + } + + mutex_lock(&mtd_partitions_mutex); + list_add(&slave->list, &mtd_partitions); + mutex_unlock(&mtd_partitions_mutex); + + ret = add_mtd_device(&slave->mtd); + if (ret) { + mutex_lock(&mtd_partitions_mutex); + list_del(&slave->list); + mutex_unlock(&mtd_partitions_mutex); + + free_partition(slave); + goto err_del_partitions; + } + + mtd_add_partition_attrs(slave); + /* Look for subpartitions */ + parse_mtd_partitions(&slave->mtd, parts[i].types, NULL); + + cur_offset = slave->offset + slave->mtd.size; + } + + return 0; + +err_del_partitions: + del_mtd_partitions(master); + + return ret; +} + +static DEFINE_SPINLOCK(part_parser_lock); +static LIST_HEAD(part_parsers); + +static struct mtd_part_parser *mtd_part_parser_get(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; +} + +static inline void mtd_part_parser_put(const struct mtd_part_parser *p) +{ + module_put(p->owner); +} + +/* + * Many partition parsers just expected the core to kfree() all their data in + * one chunk. Do that by default. + */ +static void mtd_part_parser_cleanup_default(const struct mtd_partition *pparts, + int nr_parts) +{ + kfree(pparts); +} + +int __register_mtd_parser(struct mtd_part_parser *p, struct module *owner) +{ + p->owner = owner; + + if (!p->cleanup) + p->cleanup = &mtd_part_parser_cleanup_default; + + spin_lock(&part_parser_lock); + list_add(&p->list, &part_parsers); + spin_unlock(&part_parser_lock); + + return 0; +} +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 +}; + +/* Check DT only when looking for subpartitions. */ +static const char * const default_subpartition_types[] = { + "ofpart", + NULL +}; + +static int mtd_part_do_parse(struct mtd_part_parser *parser, + struct mtd_info *master, + struct mtd_partitions *pparts, + struct mtd_part_parser_data *data) +{ + int ret; + + ret = (*parser->parse_fn)(master, &pparts->parts, data); + pr_debug("%s: parser %s: %i\n", master->name, parser->name, ret); + if (ret <= 0) + return ret; + + pr_notice("%d %s partitions found on MTD device %s\n", ret, + parser->name, master->name); + + pparts->nr_parts = ret; + pparts->parser = parser; + + return ret; +} + +/** + * mtd_part_get_compatible_parser - find MTD parser by a compatible string + * + * @compat: compatible string describing partitions in a device tree + * + * MTD parsers can specify supported partitions by providing a table of + * compatibility strings. This function finds a parser that advertises support + * for a passed value of "compatible". + */ +static struct mtd_part_parser *mtd_part_get_compatible_parser(const char *compat) +{ + struct mtd_part_parser *p, *ret = NULL; + + spin_lock(&part_parser_lock); + + list_for_each_entry(p, &part_parsers, list) { + const struct of_device_id *matches; + + matches = p->of_match_table; + if (!matches) + continue; + + for (; matches->compatible[0]; matches++) { + if (!strcmp(matches->compatible, compat) && + try_module_get(p->owner)) { + ret = p; + break; + } + } + + if (ret) + break; + } + + spin_unlock(&part_parser_lock); + + return ret; +} + +static int mtd_part_of_parse(struct mtd_info *master, + struct mtd_partitions *pparts) +{ + struct mtd_part_parser *parser; + struct device_node *np; + struct property *prop; + const char *compat; + const char *fixed = "fixed-partitions"; + int ret, err = 0; + + np = mtd_get_of_node(master); + if (mtd_is_partition(master)) + of_node_get(np); + else + np = of_get_child_by_name(np, "partitions"); + + of_property_for_each_string(np, "compatible", prop, compat) { + parser = mtd_part_get_compatible_parser(compat); + if (!parser) + continue; + ret = mtd_part_do_parse(parser, master, pparts, NULL); + if (ret > 0) { + of_node_put(np); + return ret; + } + mtd_part_parser_put(parser); + if (ret < 0 && !err) + err = ret; + } + of_node_put(np); + + /* + * For backward compatibility we have to try the "fixed-partitions" + * parser. It supports old DT format with partitions specified as a + * direct subnodes of a flash device DT node without any compatibility + * specified we could match. + */ + parser = mtd_part_parser_get(fixed); + if (!parser && !request_module("%s", fixed)) + parser = mtd_part_parser_get(fixed); + if (parser) { + ret = mtd_part_do_parse(parser, master, pparts, NULL); + if (ret > 0) + return ret; + mtd_part_parser_put(parser); + if (ret < 0 && !err) + err = ret; + } + + return err; +} + +/** + * parse_mtd_partitions - parse and register MTD partitions + * + * @master: the master partition (describes whole MTD device) + * @types: names of partition parsers to try or %NULL + * @data: MTD partition parser-specific data + * + * This function tries to find & register partitions 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 number of found partitions otherwise + */ +int parse_mtd_partitions(struct mtd_info *master, const char *const *types, + struct mtd_part_parser_data *data) +{ + struct mtd_partitions pparts = { }; + struct mtd_part_parser *parser; + int ret, err = 0; + + if (!types) + types = mtd_is_partition(master) ? default_subpartition_types : + default_mtd_part_types; + + for ( ; *types; types++) { + /* + * ofpart is a special type that means OF partitioning info + * should be used. It requires a bit different logic so it is + * handled in a separated function. + */ + if (!strcmp(*types, "ofpart")) { + ret = mtd_part_of_parse(master, &pparts); + } else { + pr_debug("%s: parsing partitions %s\n", master->name, + *types); + parser = mtd_part_parser_get(*types); + if (!parser && !request_module("%s", *types)) + parser = mtd_part_parser_get(*types); + pr_debug("%s: got parser %s\n", master->name, + parser ? parser->name : NULL); + if (!parser) + continue; + ret = mtd_part_do_parse(parser, master, &pparts, data); + if (ret <= 0) + mtd_part_parser_put(parser); + } + /* Found partitions! */ + if (ret > 0) { + err = add_mtd_partitions(master, pparts.parts, + pparts.nr_parts); + mtd_part_parser_cleanup(&pparts); + return err ? err : pparts.nr_parts; + } + /* + * Stash the first error we see; only report it if no parser + * succeeds + */ + if (ret < 0 && !err) + err = ret; + } + return err; +} + +void mtd_part_parser_cleanup(struct mtd_partitions *parts) +{ + const struct mtd_part_parser *parser; + + if (!parts) + return; + + parser = parts->parser; + if (parser) { + if (parser->cleanup) + parser->cleanup(parts->parts, parts->nr_parts); + + mtd_part_parser_put(parser); + } +} + +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 mtd_get_device_size(mtd_to_part(mtd)->parent); +} +EXPORT_SYMBOL_GPL(mtd_get_device_size); |