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| author | Dan Ehrenberg <dehrenberg@chromium.org> | 2015-04-03 00:15:11 +0200 |
|---|---|---|
| committer | Brian Norris <computersforpeace@gmail.com> | 2015-04-06 02:44:02 +0200 |
| commit | a62c24d75529118d10c45350c3b75715d52ff574 (patch) | |
| tree | 6c18ffa557b84ff94dd6dedce302a556766decf7 | |
| parent | mtd: part: Create the master device node when partitioned (diff) | |
| download | linux-a62c24d75529118d10c45350c3b75715d52ff574.tar.xz linux-a62c24d75529118d10c45350c3b75715d52ff574.zip | |
mtd: part: Add sysfs variable for offset of partition
This patch makes a sysfs variable called 'offset' on each partition
which contains the offset in bytes from the beginning of the master
device that the partition starts.
Signed-off-by: Dan Ehrenberg <dehrenberg@chromium.org>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-mtd | 10 | ||||
| -rw-r--r-- | drivers/mtd/mtdpart.c | 29 |
2 files changed, 39 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-mtd b/Documentation/ABI/testing/sysfs-class-mtd index 76ee192f80a0..3b5c3bca9186 100644 --- a/Documentation/ABI/testing/sysfs-class-mtd +++ b/Documentation/ABI/testing/sysfs-class-mtd @@ -222,3 +222,13 @@ Description: The number of blocks that are marked as reserved, if any, in this partition. These are typically used to store the in-flash bad block table (BBT). + +What: /sys/class/mtd/mtdX/offset +Date: March 2015 +KernelVersion: 4.1 +Contact: linux-mtd@lists.infradead.org +Description: + For a partition, the offset of that partition from the start + of the master device in bytes. This attribute is absent on + main devices, so it can be used to distinguish between + partitions and devices that aren't partitions. diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c index a19ec5a4e409..be8034086701 100644 --- a/drivers/mtd/mtdpart.c +++ b/drivers/mtd/mtdpart.c @@ -554,6 +554,30 @@ 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 = 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 *master, const char *name, long long offset, long long length) { @@ -603,6 +627,8 @@ int mtd_add_partition(struct mtd_info *master, const char *name, add_mtd_device(&new->mtd); + mtd_add_partition_attrs(new); + return ret; err_inv: mutex_unlock(&mtd_partitions_mutex); @@ -620,6 +646,8 @@ int mtd_del_partition(struct mtd_info *master, int partno) list_for_each_entry_safe(slave, next, &mtd_partitions, list) if ((slave->master == master) && (slave->mtd.index == partno)) { + sysfs_remove_files(&slave->mtd.dev.kobj, + mtd_partition_attrs); ret = del_mtd_device(&slave->mtd); if (ret < 0) break; @@ -663,6 +691,7 @@ int add_mtd_partitions(struct mtd_info *master, mutex_unlock(&mtd_partitions_mutex); add_mtd_device(&slave->mtd); + mtd_add_partition_attrs(slave); cur_offset = slave->offset + slave->mtd.size; } |