[PATCH 1/2] mtd: prepare partition add and del functions for ioctl requests
Roman Tereshonkov
roman.tereshonkov at nokia.com
Fri Sep 17 06:31:41 EDT 2010
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 at nokia.com>
---
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 dc65585..726c287 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -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(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(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(mtd_is_master);
diff --git a/include/linux/mtd/partitions.h b/include/linux/mtd/partitions.h
index 274b619..ffab9a6 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
--
1.6.2.4
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