Commit d9d166c2 authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
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[PATCH] md: allow array level to be set textually via sysfs 



Signed-off-by: default avatarNeil Brown <neilb@suse.de>
Acked-by: default avatarGreg KH <greg@kroah.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 8bb93aac

Documentation/md.txt

+8 −0
Original line number Diff line number Diff line
@@ -189,6 +189,14 @@ All md devices contain: 
     1.2 (newer format in varying locations) or "none" indicating that

     the kernel isn't managing metadata at all.



  level

     The raid 'level' for this array.  The name will often (but not

     always) be the same as the name of the module that implements the

     level.  To be auto-loaded the module must have an alias

        md-$LEVEL  e.g. md-raid5

     This can be written only while the array is being assembled, not

     after it is started.



As component devices are added to an md array, they appear in the 'md'

directory as new directories named

      dev-XXX

drivers/md/faulty.c

+1 −0
Original line number Diff line number Diff line
@@ -342,4 +342,5 @@ module_init(raid_init); 
module_exit(raid_exit);

MODULE_LICENSE("GPL");

MODULE_ALIAS("md-personality-10"); /* faulty */

MODULE_ALIAS("md-faulty");

MODULE_ALIAS("md-level--5");

drivers/md/linear.c

+2 −1
Original line number Diff line number Diff line
@@ -376,5 +376,6 @@ static void linear_exit (void) 
module_init(linear_init);

module_exit(linear_exit);

MODULE_LICENSE("GPL");

MODULE_ALIAS("md-personality-1"); /* LINEAR - degrecated*/

MODULE_ALIAS("md-personality-1"); /* LINEAR - deprecated*/

MODULE_ALIAS("md-linear");

MODULE_ALIAS("md-level--1");

drivers/md/md.c

+48 −13
Original line number Diff line number Diff line
@@ -303,12 +303,15 @@ static mdk_rdev_t * find_rdev(mddev_t * mddev, dev_t dev) 
	return NULL;

}



static struct mdk_personality *find_pers(int level)

static struct mdk_personality *find_pers(int level, char *clevel)

{

	struct mdk_personality *pers;

	list_for_each_entry(pers, &pers_list, list)

		if (pers->level == level)

	list_for_each_entry(pers, &pers_list, list) {

		if (level != LEVEL_NONE && pers->level == level)

			return pers;

		if (strcmp(pers->name, clevel)==0)

			return pers;

	}

	return NULL;

}
@@ -715,6 +718,7 @@ static int super_90_validate(mddev_t *mddev, mdk_rdev_t *rdev) 
		mddev->ctime = sb->ctime;

		mddev->utime = sb->utime;

		mddev->level = sb->level;

		mddev->clevel[0] = 0;

		mddev->layout = sb->layout;

		mddev->raid_disks = sb->raid_disks;

		mddev->size = sb->size;
@@ -1051,6 +1055,7 @@ static int super_1_validate(mddev_t *mddev, mdk_rdev_t *rdev) 
		mddev->ctime = le64_to_cpu(sb->ctime) & ((1ULL << 32)-1);

		mddev->utime = le64_to_cpu(sb->utime) & ((1ULL << 32)-1);

		mddev->level = le32_to_cpu(sb->level);

		mddev->clevel[0] = 0;

		mddev->layout = le32_to_cpu(sb->layout);

		mddev->raid_disks = le32_to_cpu(sb->raid_disks);

		mddev->size = le64_to_cpu(sb->size)/2;
@@ -1774,15 +1779,36 @@ static ssize_t 
level_show(mddev_t *mddev, char *page)

{

	struct mdk_personality *p = mddev->pers;

	if (p == NULL && mddev->raid_disks == 0)

		return 0;

	if (mddev->level >= 0)

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

	else

	if (p)

		return sprintf(page, "%s\n", p->name);

	else if (mddev->clevel[0])

		return sprintf(page, "%s\n", mddev->clevel);

	else if (mddev->level != LEVEL_NONE)

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

	else

		return 0;

}



static ssize_t

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

{

	int rv = len;

	if (mddev->pers)

		return -EBUSY;

	if (len == 0)

		return 0;

	if (len >= sizeof(mddev->clevel))

		return -ENOSPC;

	strncpy(mddev->clevel, buf, len);

	if (mddev->clevel[len-1] == '\n')

		len--;

	mddev->clevel[len] = 0;

	mddev->level = LEVEL_NONE;

	return rv;

}



static struct md_sysfs_entry md_level = __ATTR_RO(level);

static struct md_sysfs_entry md_level =

__ATTR(level, 0644, level_show, level_store);



static ssize_t

raid_disks_show(mddev_t *mddev, char *page)
@@ -2158,7 +2184,10 @@ static int do_md_run(mddev_t * mddev) 
	}



#ifdef CONFIG_KMOD

	if (mddev->level != LEVEL_NONE)

		request_module("md-level-%d", mddev->level);

	else if (mddev->clevel[0])

		request_module("md-%s", mddev->clevel);

#endif



	/*
@@ -2180,15 +2209,21 @@ static int do_md_run(mddev_t * mddev) 
		return -ENOMEM;



	spin_lock(&pers_lock);

	pers = find_pers(mddev->level);

	pers = find_pers(mddev->level, mddev->clevel);

	if (!pers || !try_module_get(pers->owner)) {

		spin_unlock(&pers_lock);

		if (mddev->level != LEVEL_NONE)

			printk(KERN_WARNING "md: personality for level %d is not loaded!\n",

			       mddev->level);

		else

			printk(KERN_WARNING "md: personality for level %s is not loaded!\n",

			       mddev->clevel);

		return -EINVAL;

	}

	mddev->pers = pers;

	spin_unlock(&pers_lock);

	mddev->level = pers->level;

	strlcpy(mddev->clevel, pers->name, sizeof(mddev->clevel));



	mddev->recovery = 0;

	mddev->resync_max_sectors = mddev->size << 1; /* may be over-ridden by personality */

drivers/md/multipath.c

+1 −0
Original line number Diff line number Diff line
@@ -578,4 +578,5 @@ module_init(multipath_init); 
module_exit(multipath_exit);

MODULE_LICENSE("GPL");

MODULE_ALIAS("md-personality-7"); /* MULTIPATH */

MODULE_ALIAS("md-multipath");

MODULE_ALIAS("md-level--4");