From 5daa7b21496aebf057c12be03038e7220e33353b Mon Sep 17 00:00:00 2001 From: Roman Tereshonkov Date: Fri, 17 Sep 2010 13:31:41 +0300 Subject: [PATCH] mtd: prepare partition add and del functions for ioctl requests mtd_is_master, mtd_add_partition and mtd_del_partition functions are added to give the possibility of partition manipulation by ioctl request. The old partition add function is modified to fit the dynamic allocation. Signed-off-by: Roman Tereshonkov Signed-off-by: Artem Bityutskiy Signed-off-by: David Woodhouse --- drivers/mtd/mtdpart.c | 154 +++++++++++++++++++++++++++++---- include/linux/mtd/partitions.h | 5 ++ 2 files changed, 141 insertions(+), 18 deletions(-) diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c index dc6558568876..79e3689f1e16 100644 --- a/drivers/mtd/mtdpart.c +++ b/drivers/mtd/mtdpart.c @@ -29,9 +29,11 @@ #include #include #include +#include /* Our partition linked list */ static LIST_HEAD(mtd_partitions); +static DEFINE_MUTEX(mtd_partitions_mutex); /* Our partition node structure */ struct mtd_part { @@ -326,6 +328,12 @@ static int part_block_markbad(struct mtd_info *mtd, loff_t ofs) 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. @@ -334,33 +342,42 @@ static int part_block_markbad(struct mtd_info *mtd, loff_t ofs) 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); - del_mtd_device(&slave->mtd); - kfree(slave); + free_partition(slave); } + mutex_unlock(&mtd_partitions_mutex); - return 0; + return err; } EXPORT_SYMBOL(del_mtd_partitions); -static struct mtd_part *add_one_partition(struct mtd_info *master, - const struct mtd_partition *part, int partno, - uint64_t cur_offset) +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); - if (!slave) { + name = kstrdup(part->name, GFP_KERNEL); + if (!name || !slave) { printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n", - master->name); - del_mtd_partitions(master); - return NULL; + master->name); + kfree(name); + kfree(slave); + return ERR_PTR(-ENOMEM); } - list_add(&slave->list, &mtd_partitions); /* set up the MTD object for this partition */ slave->mtd.type = master->type; @@ -371,7 +388,7 @@ static struct mtd_part *add_one_partition(struct mtd_info *master, slave->mtd.oobavail = master->oobavail; slave->mtd.subpage_sft = master->subpage_sft; - slave->mtd.name = part->name; + slave->mtd.name = name; slave->mtd.owner = master->owner; slave->mtd.backing_dev_info = master->backing_dev_info; @@ -518,12 +535,89 @@ static struct mtd_part *add_one_partition(struct mtd_info *master, } out_register: - /* register our partition */ - add_mtd_device(&slave->mtd); - return slave; } +int mtd_add_partition(struct mtd_info *master, 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); + /* * 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 @@ -544,9 +638,16 @@ int add_mtd_partitions(struct mtd_info *master, printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name); for (i = 0; i < nbparts; i++) { - slave = add_one_partition(master, parts + i, i, cur_offset); - if (!slave) - return -ENOMEM; + 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; } @@ -618,3 +719,20 @@ int parse_mtd_partitions(struct mtd_info *master, const char **types, return ret; } EXPORT_SYMBOL_GPL(parse_mtd_partitions); + +int mtd_is_master(struct mtd_info *mtd) +{ + struct mtd_part *part; + int nopart = 0; + + mutex_lock(&mtd_partitions_mutex); + list_for_each_entry(part, &mtd_partitions, list) + if (&part->mtd == mtd) { + nopart = 1; + break; + } + mutex_unlock(&mtd_partitions_mutex); + + return nopart; +} +EXPORT_SYMBOL_GPL(mtd_is_master); diff --git a/include/linux/mtd/partitions.h b/include/linux/mtd/partitions.h index 930c8ac198db..2b54316591d2 100644 --- a/include/linux/mtd/partitions.h +++ b/include/linux/mtd/partitions.h @@ -89,4 +89,9 @@ static inline int mtd_has_cmdlinepart(void) { return 1; } static inline int mtd_has_cmdlinepart(void) { return 0; } #endif +int mtd_is_master(struct mtd_info *mtd); +int mtd_add_partition(struct mtd_info *master, char *name, + long long offset, long long length); +int mtd_del_partition(struct mtd_info *master, int partno); + #endif -- 2.39.5