diff options
| -rw-r--r-- | Documentation/md.txt | 72 | ||||
| -rw-r--r-- | drivers/md/md.c | 70 |
2 files changed, 107 insertions, 35 deletions
diff --git a/Documentation/md.txt b/Documentation/md.txt index 2202f5dc8ac2..5818628207b5 100644 --- a/Documentation/md.txt +++ b/Documentation/md.txt @@ -178,6 +178,21 @@ All md devices contain: The size should be at least PAGE_SIZE (4k) and should be a power of 2. This can only be set while assembling an array + 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. + + reshape_position + This is either "none" or a sector number within the devices of + the array where "reshape" is up to. If this is set, the three + attributes mentioned above (raid_disks, chunk_size, layout) can + potentially have 2 values, an old and a new value. If these + values differ, reading the attribute returns + new (old) + and writing will effect the 'new' value, leaving the 'old' + unchanged. + component_size For arrays with data redundancy (i.e. not raid0, linear, faulty, multipath), all components must be the same size - or at least @@ -193,11 +208,6 @@ All md devices contain: 1.2 (newer format in varying locations) or "none" indicating that the kernel isn't managing metadata at all. - 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. - 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 @@ -259,29 +269,6 @@ All md devices contain: like active, but no writes have been seen for a while (safe_mode_delay). - sync_speed_min - sync_speed_max - This are similar to /proc/sys/dev/raid/speed_limit_{min,max} - however they only apply to the particular array. - If no value has been written to these, of if the word 'system' - is written, then the system-wide value is used. If a value, - in kibibytes-per-second is written, then it is used. - When the files are read, they show the currently active value - followed by "(local)" or "(system)" depending on whether it is - a locally set or system-wide value. - - sync_completed - This shows the number of sectors that have been completed of - whatever the current sync_action is, followed by the number of - sectors in total that could need to be processed. The two - numbers are separated by a '/' thus effectively showing one - value, a fraction of the process that is complete. - - sync_speed - This shows the current actual speed, in K/sec, of the current - sync_action. It is averaged over the last 30 seconds. - - As component devices are added to an md array, they appear in the 'md' directory as new directories named dev-XXX @@ -412,6 +399,35 @@ also have Note that the numbers are 'bit' numbers, not 'block' numbers. They should be scaled by the bitmap_chunksize. + sync_speed_min + sync_speed_max + This are similar to /proc/sys/dev/raid/speed_limit_{min,max} + however they only apply to the particular array. + If no value has been written to these, of if the word 'system' + is written, then the system-wide value is used. If a value, + in kibibytes-per-second is written, then it is used. + When the files are read, they show the currently active value + followed by "(local)" or "(system)" depending on whether it is + a locally set or system-wide value. + + sync_completed + This shows the number of sectors that have been completed of + whatever the current sync_action is, followed by the number of + sectors in total that could need to be processed. The two + numbers are separated by a '/' thus effectively showing one + value, a fraction of the process that is complete. + + sync_speed + This shows the current actual speed, in K/sec, of the current + sync_action. It is averaged over the last 30 seconds. + + suspend_lo + suspend_hi + The two values, given as numbers of sectors, indicate a range + within the array where IO will be blocked. This is currently + only supported for raid4/5/6. + + Each active md device may also have attributes specific to the personality module that manages it. These are specific to the implementation of the module and could diff --git a/drivers/md/md.c b/drivers/md/md.c index bad324171cad..65814b0340cb 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -274,6 +274,7 @@ static mddev_t * mddev_find(dev_t unit) atomic_set(&new->active, 1); spin_lock_init(&new->write_lock); init_waitqueue_head(&new->sb_wait); + new->reshape_position = MaxSector; new->queue = blk_alloc_queue(GFP_KERNEL); if (!new->queue) { @@ -2242,6 +2243,10 @@ static ssize_t layout_show(mddev_t *mddev, char *page) { /* just a number, not meaningful for all levels */ + if (mddev->reshape_position != MaxSector && + mddev->layout != mddev->new_layout) + return sprintf(page, "%d (%d)\n", + mddev->new_layout, mddev->layout); return sprintf(page, "%d\n", mddev->layout); } @@ -2250,13 +2255,16 @@ 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; + if (mddev->pers) + return -EBUSY; + if (mddev->reshape_position != MaxSector) + mddev->new_layout = n; + else + mddev->layout = n; return len; } static struct md_sysfs_entry md_layout = @@ -2268,6 +2276,10 @@ raid_disks_show(mddev_t *mddev, char *page) { if (mddev->raid_disks == 0) return 0; + if (mddev->reshape_position != MaxSector && + mddev->delta_disks != 0) + return sprintf(page, "%d (%d)\n", mddev->raid_disks, + mddev->raid_disks - mddev->delta_disks); return sprintf(page, "%d\n", mddev->raid_disks); } @@ -2285,7 +2297,11 @@ raid_disks_store(mddev_t *mddev, const char *buf, size_t len) if (mddev->pers) rv = update_raid_disks(mddev, n); - else + else if (mddev->reshape_position != MaxSector) { + int olddisks = mddev->raid_disks - mddev->delta_disks; + mddev->delta_disks = n - olddisks; + mddev->raid_disks = n; + } else mddev->raid_disks = n; return rv ? rv : len; } @@ -2295,6 +2311,10 @@ __ATTR(raid_disks, S_IRUGO|S_IWUSR, raid_disks_show, raid_disks_store); static ssize_t chunk_size_show(mddev_t *mddev, char *page) { + if (mddev->reshape_position != MaxSector && + mddev->chunk_size != mddev->new_chunk) + return sprintf(page, "%d (%d)\n", mddev->new_chunk, + mddev->chunk_size); return sprintf(page, "%d\n", mddev->chunk_size); } @@ -2305,12 +2325,15 @@ chunk_size_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->chunk_size = n; + if (mddev->pers) + return -EBUSY; + else if (mddev->reshape_position != MaxSector) + mddev->new_chunk = n; + else + mddev->chunk_size = n; return len; } static struct md_sysfs_entry md_chunk_size = @@ -2896,6 +2919,37 @@ suspend_hi_store(mddev_t *mddev, const char *buf, size_t len) static struct md_sysfs_entry md_suspend_hi = __ATTR(suspend_hi, S_IRUGO|S_IWUSR, suspend_hi_show, suspend_hi_store); +static ssize_t +reshape_position_show(mddev_t *mddev, char *page) +{ + if (mddev->reshape_position != MaxSector) + return sprintf(page, "%llu\n", + (unsigned long long)mddev->reshape_position); + strcpy(page, "none\n"); + return 5; +} + +static ssize_t +reshape_position_store(mddev_t *mddev, const char *buf, size_t len) +{ + char *e; + unsigned long long new = simple_strtoull(buf, &e, 10); + if (mddev->pers) + return -EBUSY; + if (buf == e || (*e && *e != '\n')) + return -EINVAL; + mddev->reshape_position = new; + mddev->delta_disks = 0; + mddev->new_level = mddev->level; + mddev->new_layout = mddev->layout; + mddev->new_chunk = mddev->chunk_size; + return len; +} + +static struct md_sysfs_entry md_reshape_position = +__ATTR(reshape_position, S_IRUGO|S_IWUSR, reshape_position_show, + reshape_position_store); + static struct attribute *md_default_attrs[] = { &md_level.attr, @@ -2908,6 +2962,7 @@ static struct attribute *md_default_attrs[] = { &md_new_device.attr, &md_safe_delay.attr, &md_array_state.attr, + &md_reshape_position.attr, NULL, }; @@ -3446,6 +3501,7 @@ static int do_md_stop(mddev_t * mddev, int mode) mddev->size = 0; mddev->raid_disks = 0; mddev->recovery_cp = 0; + mddev->reshape_position = MaxSector; } else if (mddev->pers) printk(KERN_INFO "md: %s switched to read-only mode.\n", |