From 06e3c817b750c131a20e82eed57a17841ea88ed2 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Sat, 12 Dec 2009 21:17:12 -0700 Subject: [PATCH] md: add 'recovery_start' per-device sysfs attribute Enable external metadata arrays to manage rebuild checkpointing via a md/dev-XXX/recovery_start attribute which reflects rdev->recovery_offset Also update resync_start_store to allow 'none' to be written, for consistency. Signed-off-by: Dan Williams Signed-off-by: NeilBrown --- Documentation/md.txt | 27 +++++++++++++++++++++++---- drivers/md/md.c | 41 ++++++++++++++++++++++++++++++++++++++++- 2 files changed, 63 insertions(+), 5 deletions(-) diff --git a/Documentation/md.txt b/Documentation/md.txt index 21d26fb5d02be..188f4768f1d58 100644 --- a/Documentation/md.txt +++ b/Documentation/md.txt @@ -233,9 +233,9 @@ All md devices contain: resync_start The point at which resync should start. If no resync is needed, - this will be a very large number. At array creation it will - default to 0, though starting the array as 'clean' will - set it much larger. + this will be a very large number (or 'none' since 2.6.30-rc1). At + array creation it will default to 0, though starting the array as + 'clean' will set it much larger. new_dev This file can be written but not read. The value written should @@ -379,8 +379,9 @@ Each directory contains: Writing "writemostly" sets the writemostly flag. Writing "-writemostly" clears the writemostly flag. Writing "blocked" sets the "blocked" flag. - Writing "-blocked" clear the "blocked" flag and allows writes + Writing "-blocked" clears the "blocked" flag and allows writes to complete. + Writing "in_sync" sets the in_sync flag. This file responds to select/poll. Any change to 'faulty' or 'blocked' causes an event. @@ -417,6 +418,24 @@ Each directory contains: array. If a value less than the current component_size is written, it will be rejected. + recovery_start + + When the device is not 'in_sync', this records the number of + sectors from the start of the device which are known to be + correct. This is normally zero, but during a recovery + operation is will steadily increase, and if the recovery is + interrupted, restoring this value can cause recovery to + avoid repeating the earlier blocks. With v1.x metadata, this + value is saved and restored automatically. + + This can be set whenever the device is not an active member of + the array, either before the array is activated, or before + the 'slot' is set. + + Setting this to 'none' is equivalent to setting 'in_sync'. + Setting to any other value also clears the 'in_sync' flag. + + An active md device will also contain and entry for each active device in the array. These are named diff --git a/drivers/md/md.c b/drivers/md/md.c index ea64a68e9c751..e1f3c1715cca2 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2551,12 +2551,49 @@ rdev_size_store(mdk_rdev_t *rdev, const char *buf, size_t len) static struct rdev_sysfs_entry rdev_size = __ATTR(size, S_IRUGO|S_IWUSR, rdev_size_show, rdev_size_store); + +static ssize_t recovery_start_show(mdk_rdev_t *rdev, char *page) +{ + unsigned long long recovery_start = rdev->recovery_offset; + + if (test_bit(In_sync, &rdev->flags) || + recovery_start == MaxSector) + return sprintf(page, "none\n"); + + return sprintf(page, "%llu\n", recovery_start); +} + +static ssize_t recovery_start_store(mdk_rdev_t *rdev, const char *buf, size_t len) +{ + unsigned long long recovery_start; + + if (cmd_match(buf, "none")) + recovery_start = MaxSector; + else if (strict_strtoull(buf, 10, &recovery_start)) + return -EINVAL; + + if (rdev->mddev->pers && + rdev->raid_disk >= 0) + return -EBUSY; + + rdev->recovery_offset = recovery_start; + if (recovery_start == MaxSector) + set_bit(In_sync, &rdev->flags); + else + clear_bit(In_sync, &rdev->flags); + return len; +} + +static struct rdev_sysfs_entry rdev_recovery_start = +__ATTR(recovery_start, S_IRUGO|S_IWUSR, recovery_start_show, recovery_start_store); + static struct attribute *rdev_default_attrs[] = { &rdev_state.attr, &rdev_errors.attr, &rdev_slot.attr, &rdev_offset.attr, &rdev_size.attr, + &rdev_recovery_start.attr, NULL, }; static ssize_t @@ -3101,7 +3138,9 @@ resync_start_store(mddev_t *mddev, const char *buf, size_t len) if (mddev->pers) return -EBUSY; - if (!*buf || (*e && *e != '\n')) + if (cmd_match(buf, "none")) + n = MaxSector; + else if (!*buf || (*e && *e != '\n')) return -EINVAL; mddev->recovery_cp = n; -- 2.39.5