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 <roman.tereshonkov@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This commit is contained in:
Roman Tereshonkov 2010-09-17 13:31:41 +03:00 committed by David Woodhouse
parent 93ac5a552c
commit 5daa7b2149
2 changed files with 141 additions and 18 deletions

View File

@ -29,9 +29,11 @@
#include <linux/kmod.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/err.h>
/* 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);

View File

@ -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