| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * 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> |
| */ |
| |
| #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 <linux/of_platform.h> |
| |
| #include "mtdcore.h" |
| |
| /* |
| * MTD methods which simply translate the effective address and pass through |
| * to the _real_ device. |
| */ |
| |
| static inline void free_partition(struct mtd_info *mtd) |
| { |
| kfree(mtd->name); |
| kfree(mtd); |
| } |
| |
| void release_mtd_partition(struct mtd_info *mtd) |
| { |
| WARN_ON(!list_empty(&mtd->part.node)); |
| free_partition(mtd); |
| } |
| |
| static struct mtd_info *allocate_partition(struct mtd_info *parent, |
| const struct mtd_partition *part, |
| int partno, uint64_t cur_offset) |
| { |
| struct mtd_info *master = mtd_get_master(parent); |
| int wr_alignment = (parent->flags & MTD_NO_ERASE) ? |
| master->writesize : master->erasesize; |
| u64 parent_size = mtd_is_partition(parent) ? |
| parent->part.size : parent->size; |
| struct mtd_info *child; |
| u32 remainder; |
| char *name; |
| u64 tmp; |
| |
| /* allocate the partition structure */ |
| child = kzalloc(sizeof(*child), GFP_KERNEL); |
| name = kstrdup(part->name, GFP_KERNEL); |
| if (!name || !child) { |
| printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n", |
| parent->name); |
| kfree(name); |
| kfree(child); |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| /* set up the MTD object for this partition */ |
| child->type = parent->type; |
| child->part.flags = parent->flags & ~part->mask_flags; |
| child->part.flags |= part->add_flags; |
| child->flags = child->part.flags; |
| child->part.size = part->size; |
| child->writesize = parent->writesize; |
| child->writebufsize = parent->writebufsize; |
| child->oobsize = parent->oobsize; |
| child->oobavail = parent->oobavail; |
| child->subpage_sft = parent->subpage_sft; |
| |
| child->name = name; |
| child->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 parent and its partitions in sysfs. |
| */ |
| child->dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) || mtd_is_partition(parent) ? |
| &parent->dev : parent->dev.parent; |
| child->dev.of_node = part->of_node; |
| child->parent = parent; |
| child->part.offset = part->offset; |
| INIT_LIST_HEAD(&child->partitions); |
| |
| if (child->part.offset == MTDPART_OFS_APPEND) |
| child->part.offset = cur_offset; |
| if (child->part.offset == MTDPART_OFS_NXTBLK) { |
| tmp = cur_offset; |
| child->part.offset = cur_offset; |
| remainder = do_div(tmp, wr_alignment); |
| if (remainder) { |
| child->part.offset += wr_alignment - remainder; |
| printk(KERN_NOTICE "Moving partition %d: " |
| "0x%012llx -> 0x%012llx\n", partno, |
| (unsigned long long)cur_offset, |
| child->part.offset); |
| } |
| } |
| if (child->part.offset == MTDPART_OFS_RETAIN) { |
| child->part.offset = cur_offset; |
| if (parent_size - child->part.offset >= child->part.size) { |
| child->part.size = parent_size - child->part.offset - |
| child->part.size; |
| } else { |
| printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n", |
| part->name, parent_size - child->part.offset, |
| child->part.size); |
| /* register to preserve ordering */ |
| goto out_register; |
| } |
| } |
| if (child->part.size == MTDPART_SIZ_FULL) |
| child->part.size = parent_size - child->part.offset; |
| |
| printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", |
| child->part.offset, child->part.offset + child->part.size, |
| child->name); |
| |
| /* let's do some sanity checks */ |
| if (child->part.offset >= parent_size) { |
| /* let's register it anyway to preserve ordering */ |
| child->part.offset = 0; |
| child->part.size = 0; |
| |
| /* Initialize ->erasesize to make add_mtd_device() happy. */ |
| child->erasesize = parent->erasesize; |
| printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n", |
| part->name); |
| goto out_register; |
| } |
| if (child->part.offset + child->part.size > parent->size) { |
| child->part.size = parent_size - child->part.offset; |
| printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n", |
| part->name, parent->name, child->part.size); |
| } |
| |
| if (parent->numeraseregions > 1) { |
| /* Deal with variable erase size stuff */ |
| int i, max = parent->numeraseregions; |
| u64 end = child->part.offset + child->part.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 <= child->part.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 (child->erasesize < regions[i].erasesize) |
| child->erasesize = regions[i].erasesize; |
| } |
| BUG_ON(child->erasesize == 0); |
| } else { |
| /* Single erase size */ |
| child->erasesize = master->erasesize; |
| } |
| |
| /* |
| * Child erasesize might differ from the parent one if the parent |
| * exposes several regions with different erasesize. Adjust |
| * wr_alignment accordingly. |
| */ |
| if (!(child->flags & MTD_NO_ERASE)) |
| wr_alignment = child->erasesize; |
| |
| tmp = mtd_get_master_ofs(child, 0); |
| remainder = do_div(tmp, wr_alignment); |
| if ((child->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 */ |
| child->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 = mtd_get_master_ofs(child, 0) + child->part.size; |
| remainder = do_div(tmp, wr_alignment); |
| if ((child->flags & MTD_WRITEABLE) && remainder) { |
| child->flags &= ~MTD_WRITEABLE; |
| printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase/write block -- force read-only\n", |
| part->name); |
| } |
| |
| child->size = child->part.size; |
| child->ecc_step_size = parent->ecc_step_size; |
| child->ecc_strength = parent->ecc_strength; |
| child->bitflip_threshold = parent->bitflip_threshold; |
| |
| if (master->_block_isbad) { |
| uint64_t offs = 0; |
| |
| while (offs < child->part.size) { |
| if (mtd_block_isreserved(child, offs)) |
| child->ecc_stats.bbtblocks++; |
| else if (mtd_block_isbad(child, offs)) |
| child->ecc_stats.badblocks++; |
| offs += child->erasesize; |
| } |
| } |
| |
| out_register: |
| return child; |
| } |
| |
| static ssize_t offset_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct mtd_info *mtd = dev_get_drvdata(dev); |
| |
| return sysfs_emit(buf, "%lld\n", mtd->part.offset); |
| } |
| static DEVICE_ATTR_RO(offset); /* mtd partition offset */ |
| |
| static const struct attribute *mtd_partition_attrs[] = { |
| &dev_attr_offset.attr, |
| NULL |
| }; |
| |
| static int mtd_add_partition_attrs(struct mtd_info *new) |
| { |
| int ret = sysfs_create_files(&new->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_info *master = mtd_get_master(parent); |
| u64 parent_size = mtd_is_partition(parent) ? |
| parent->part.size : parent->size; |
| struct mtd_partition part; |
| struct mtd_info *child; |
| 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; |
| |
| child = allocate_partition(parent, &part, -1, offset); |
| if (IS_ERR(child)) |
| return PTR_ERR(child); |
| |
| mutex_lock(&master->master.partitions_lock); |
| list_add_tail(&child->part.node, &parent->partitions); |
| mutex_unlock(&master->master.partitions_lock); |
| |
| ret = add_mtd_device(child); |
| if (ret) |
| goto err_remove_part; |
| |
| mtd_add_partition_attrs(child); |
| |
| return 0; |
| |
| err_remove_part: |
| mutex_lock(&master->master.partitions_lock); |
| list_del(&child->part.node); |
| mutex_unlock(&master->master.partitions_lock); |
| |
| free_partition(child); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(mtd_add_partition); |
| |
| /** |
| * __mtd_del_partition - delete MTD partition |
| * |
| * @mtd: MTD structure to be deleted |
| * |
| * This function must be called with the partitions mutex locked. |
| */ |
| static int __mtd_del_partition(struct mtd_info *mtd) |
| { |
| struct mtd_info *child, *next; |
| int err; |
| |
| list_for_each_entry_safe(child, next, &mtd->partitions, part.node) { |
| err = __mtd_del_partition(child); |
| if (err) |
| return err; |
| } |
| |
| sysfs_remove_files(&mtd->dev.kobj, mtd_partition_attrs); |
| |
| list_del_init(&mtd->part.node); |
| err = del_mtd_device(mtd); |
| if (err) |
| return err; |
| |
| return 0; |
| } |
| |
| /* |
| * This function unregisters and destroy all slave MTD objects which are |
| * attached to the given MTD object, recursively. |
| */ |
| static int __del_mtd_partitions(struct mtd_info *mtd) |
| { |
| struct mtd_info *child, *next; |
| int ret, err = 0; |
| |
| list_for_each_entry_safe(child, next, &mtd->partitions, part.node) { |
| if (mtd_has_partitions(child)) |
| __del_mtd_partitions(child); |
| |
| pr_info("Deleting %s MTD partition\n", child->name); |
| list_del_init(&child->part.node); |
| ret = del_mtd_device(child); |
| if (ret < 0) { |
| pr_err("Error when deleting partition \"%s\" (%d)\n", |
| child->name, ret); |
| err = ret; |
| continue; |
| } |
| } |
| |
| return err; |
| } |
| |
| int del_mtd_partitions(struct mtd_info *mtd) |
| { |
| struct mtd_info *master = mtd_get_master(mtd); |
| int ret; |
| |
| pr_info("Deleting MTD partitions on \"%s\":\n", mtd->name); |
| |
| mutex_lock(&master->master.partitions_lock); |
| ret = __del_mtd_partitions(mtd); |
| mutex_unlock(&master->master.partitions_lock); |
| |
| return ret; |
| } |
| |
| int mtd_del_partition(struct mtd_info *mtd, int partno) |
| { |
| struct mtd_info *child, *master = mtd_get_master(mtd); |
| int ret = -EINVAL; |
| |
| mutex_lock(&master->master.partitions_lock); |
| list_for_each_entry(child, &mtd->partitions, part.node) { |
| if (child->index == partno) { |
| ret = __mtd_del_partition(child); |
| break; |
| } |
| } |
| mutex_unlock(&master->master.partitions_lock); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(mtd_del_partition); |
| |
| /* |
| * This function, given a parent MTD object and a partition table, creates |
| * and registers the child MTD objects which are bound to the parent according |
| * to the partition definitions. |
| * |
| * For historical reasons, this function's caller only registers the parent |
| * if the MTD_PARTITIONED_MASTER config option is set. |
| */ |
| |
| int add_mtd_partitions(struct mtd_info *parent, |
| const struct mtd_partition *parts, |
| int nbparts) |
| { |
| struct mtd_info *child, *master = mtd_get_master(parent); |
| uint64_t cur_offset = 0; |
| int i, ret; |
| |
| printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", |
| nbparts, parent->name); |
| |
| for (i = 0; i < nbparts; i++) { |
| child = allocate_partition(parent, parts + i, i, cur_offset); |
| if (IS_ERR(child)) { |
| ret = PTR_ERR(child); |
| goto err_del_partitions; |
| } |
| |
| mutex_lock(&master->master.partitions_lock); |
| list_add_tail(&child->part.node, &parent->partitions); |
| mutex_unlock(&master->master.partitions_lock); |
| |
| ret = add_mtd_device(child); |
| if (ret) { |
| mutex_lock(&master->master.partitions_lock); |
| list_del(&child->part.node); |
| mutex_unlock(&master->master.partitions_lock); |
| |
| free_partition(child); |
| goto err_del_partitions; |
| } |
| |
| mtd_add_partition_attrs(child); |
| |
| /* Look for subpartitions */ |
| parse_mtd_partitions(child, parts[i].types, NULL); |
| |
| cur_offset = child->part.offset + child->part.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 device_node *child; |
| struct property *prop; |
| struct device *dev; |
| const char *compat; |
| const char *fixed = "fixed-partitions"; |
| int ret, err = 0; |
| |
| dev = &master->dev; |
| /* Use parent device (controller) if the top level MTD is not registered */ |
| if (!IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) && !mtd_is_partition(master)) |
| dev = master->dev.parent; |
| |
| np = mtd_get_of_node(master); |
| if (mtd_is_partition(master)) |
| of_node_get(np); |
| else |
| np = of_get_child_by_name(np, "partitions"); |
| |
| /* |
| * Don't create devices that are added to a bus but will never get |
| * probed. That'll cause fw_devlink to block probing of consumers of |
| * this partition until the partition device is probed. |
| */ |
| for_each_child_of_node(np, child) |
| if (of_device_is_compatible(child, "nvmem-cells")) |
| of_node_set_flag(child, OF_POPULATED); |
| |
| 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_platform_populate(np, NULL, NULL, dev); |
| of_node_put(np); |
| return ret; |
| } |
| mtd_part_parser_put(parser); |
| if (ret < 0 && !err) |
| err = ret; |
| } |
| of_platform_populate(np, NULL, NULL, dev); |
| 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); |
| } |
| } |
| |
| /* Returns the size of the entire flash chip */ |
| uint64_t mtd_get_device_size(const struct mtd_info *mtd) |
| { |
| struct mtd_info *master = mtd_get_master((struct mtd_info *)mtd); |
| |
| return master->size; |
| } |
| EXPORT_SYMBOL_GPL(mtd_get_device_size); |