[PATCH 1/2] md: Add configurability for consistency check feature
From: Ralph Mueck <hidden>
Date: 2014-03-17 15:00:40
Also in:
lkml
Subsystem:
software raid (multiple disks) support, the rest · Maintainers:
Song Liu, Yu Kuai, Linus Torvalds
This patch adds sysfs configurability for the md level-1 RAID consistency check. The feature introduces a new attribute in sysfs named "safe_read". To toggle consistency checks on/off, simply echo safe_read in /sys/block/md*/md/safe_read. Signed-off-by: Ralph Mueck <redacted> Signed-off-by: Matthias Oefelein <redacted> --- drivers/md/md.c | 27 +++++++++++++++++++++++++++ drivers/md/md.h | 3 +++ 2 files changed, 30 insertions(+)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 4ad5cc4..5cc9a00 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c@@ -4652,6 +4652,32 @@ static struct md_sysfs_entry md_array_size = __ATTR(array_size, S_IRUGO|S_IWUSR, array_size_show, array_size_store); +static ssize_t +safe_read_show(struct mddev *mddev, char *page) +{ + if(mddev->safe_read) + return sprintf(page, "enabled\n"); + else + return sprintf(page, "disabled\n"); +} + +static ssize_t +safe_read_store(struct mddev *mddev, const char *buf, size_t len) +{ + if(mddev->pers->level != 1) { + printk(KERN_NOTICE "RAID level not supported!\n"); + return len; + } + if (strncmp(buf, "safe_read", 9) == 0) { + mddev->safe_read = !mddev->safe_read; + } + return len; +} + +static struct md_sysfs_entry md_safe_read = +__ATTR(safe_read, S_IRUGO|S_IWUSR, safe_read_show, + safe_read_store); + static struct attribute *md_default_attrs[] = { &md_level.attr, &md_layout.attr,
@@ -4667,6 +4693,7 @@ static struct attribute *md_default_attrs[] = { &md_reshape_direction.attr, &md_array_size.attr, &max_corr_read_errors.attr, + &md_safe_read.attr, NULL, };
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 07bba96..7e59cf1 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h@@ -346,6 +346,9 @@ struct mddev { */ int recovery_disabled; + /* Set to 1 if the user desires a safe read (check for bitrot) */ + int safe_read; + int in_sync; /* know to not need resync */ /* 'open_mutex' avoids races between 'md_open' and 'do_md_stop', so * that we are never stopping an array while it is open.
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1.8.3.2