Commit d4dbd025 authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
Browse files

[PATCH] md: Allow raid 'layout' to be read and set via sysfs 



Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 45dc2de1

Documentation/md.txt

+5 −0
Original line number Diff line number Diff line
@@ -200,6 +200,11 @@ All md devices contain: 
     This can be written only while the array is being assembled, not

     after it is started.



  layout

     The "layout" for the array for the particular level.  This is

     simply a number that is interpretted differently by different

     levels.  It can be written while assembling an array.



   new_dev

     This file can be written but not read.  The value written should

     be a block device number as major:minor.  e.g. 8:0

drivers/md/md.c

+27 −0
Original line number Diff line number Diff line
@@ -2155,6 +2155,32 @@ level_store(mddev_t *mddev, const char *buf, size_t len) 
static struct md_sysfs_entry md_level =

__ATTR(level, 0644, level_show, level_store);





static ssize_t

layout_show(mddev_t *mddev, char *page)

{

	/* just a number, not meaningful for all levels */

	return sprintf(page, "%d\n", mddev->layout);

}



static ssize_t

layout_store(mddev_t *mddev, const char *buf, size_t len)

{

	char *e;

	unsigned long n = simple_strtoul(buf, &e, 10);

	if (mddev->pers)

		return -EBUSY;



	if (!*buf || (*e && *e != '\n'))

		return -EINVAL;



	mddev->layout = n;

	return len;

}

static struct md_sysfs_entry md_layout =

__ATTR(layout, 0655, layout_show, layout_store);





static ssize_t

raid_disks_show(mddev_t *mddev, char *page)

{
@@ -2741,6 +2767,7 @@ __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store); 


static struct attribute *md_default_attrs[] = {

	&md_level.attr,

	&md_layout.attr,

	&md_raid_disks.attr,

	&md_chunk_size.attr,

	&md_size.attr,