md: Tidy up rdev_size_store a bit:
- used strict_strtoull in place of simple_strtoull
- use my_mddev in place of rdev->mddev (they have the same value)
and more significantly,
- don't adjust mddev->size to fit, rather reject changes which make
rdev->size smaller than mddev->size
Adjusting mddev->size is a hangover from bind_rdev_to_array which
does a similar thing. But it really is a better design to insist that
mddev->size is set as required, then the rdev->sizes are set to allow
for that. The previous way invites confusion.
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/Documentation/md.txt b/Documentation/md.txt
index e06cc59..1da9d1b 100644
--- a/Documentation/md.txt
+++ b/Documentation/md.txt
@@ -347,7 +347,7 @@
for storage of data. This will normally be the same as the
component_size. This can be written while assembling an
array. If a value less than the current component_size is
- written, component_size will be reduced to this value.
+ written, it will be rejected.
An active md device will also contain and entry for each active device
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 5590cb5..95466bb 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2101,16 +2101,17 @@
static ssize_t
rdev_size_store(mdk_rdev_t *rdev, const char *buf, size_t len)
{
- char *e;
- unsigned long long size = simple_strtoull(buf, &e, 10);
+ unsigned long long size;
unsigned long long oldsize = rdev->size;
mddev_t *my_mddev = rdev->mddev;
- if (e==buf || (*e && *e != '\n'))
+ if (strict_strtoull(buf, 10, &size) < 0)
+ return -EINVAL;
+ if (size < my_mddev->size)
return -EINVAL;
if (my_mddev->pers && rdev->raid_disk >= 0) {
- if (rdev->mddev->persistent) {
- size = super_types[rdev->mddev->major_version].
+ if (my_mddev->persistent) {
+ size = super_types[my_mddev->major_version].
rdev_size_change(rdev, size);
if (!size)
return -EBUSY;
@@ -2118,12 +2119,12 @@
size = (rdev->bdev->bd_inode->i_size >> 10);
size -= rdev->data_offset/2;
}
- if (size < rdev->mddev->size)
+ if (size < my_mddev->size)
return -EINVAL; /* component must fit device */
}
rdev->size = size;
- if (size > oldsize && rdev->mddev->external) {
+ if (size > oldsize && my_mddev->external) {
/* need to check that all other rdevs with the same ->bdev
* do not overlap. We need to unlock the mddev to avoid
* a deadlock. We have already changed rdev->size, and if
@@ -2165,8 +2166,6 @@
return -EBUSY;
}
}
- if (size < my_mddev->size || my_mddev->size == 0)
- my_mddev->size = size;
return len;
}