diff options
author | Paul Clements <paul.clements@steeleye.com> | 2006-10-03 04:15:49 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-10-03 11:04:17 -0400 |
commit | 9b1d1dac181d8c1b9492e05cee660a985d035a06 (patch) | |
tree | af12b1eaac4e0f7f3528ec26a223faeabed35845 /drivers | |
parent | 76186dd8b73d2b7b9b4c8629b89c845e97009801 (diff) |
[PATCH] md: new sysfs interface for setting bits in the write-intent-bitmap
Add a new sysfs interface that allows the bitmap of an array to be dirtied.
The interface is write-only, and is used as follows:
echo "1000" > /sys/block/md2/md/bitmap
(dirty the bit for chunk 1000 [offset 0] in the in-memory and on-disk
bitmaps of array md2)
echo "1000-2000" > /sys/block/md1/md/bitmap
(dirty the bits for chunks 1000-2000 in md1's bitmap)
This is useful, for example, in cluster environments where you may need to
combine two disjoint bitmaps into one (following a server failure, after a
secondary server has taken over the array). By combining the bitmaps on
the two servers, a full resync can be avoided (This was discussed on the
list back on March 18, 2005, "[PATCH 1/2] md bitmap bug fixes" thread).
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/md/bitmap.c | 14 | ||||
-rw-r--r-- | drivers/md/md.c | 31 |
2 files changed, 45 insertions, 0 deletions
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index ecc56765d949..0a44298fb353 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c | |||
@@ -613,6 +613,7 @@ static inline unsigned long file_page_offset(unsigned long chunk) | |||
613 | static inline struct page *filemap_get_page(struct bitmap *bitmap, | 613 | static inline struct page *filemap_get_page(struct bitmap *bitmap, |
614 | unsigned long chunk) | 614 | unsigned long chunk) |
615 | { | 615 | { |
616 | if (file_page_index(chunk) >= bitmap->file_pages) return NULL; | ||
616 | return bitmap->filemap[file_page_index(chunk) - file_page_index(0)]; | 617 | return bitmap->filemap[file_page_index(chunk) - file_page_index(0)]; |
617 | } | 618 | } |
618 | 619 | ||
@@ -739,6 +740,7 @@ static void bitmap_file_set_bit(struct bitmap *bitmap, sector_t block) | |||
739 | } | 740 | } |
740 | 741 | ||
741 | page = filemap_get_page(bitmap, chunk); | 742 | page = filemap_get_page(bitmap, chunk); |
743 | if (!page) return; | ||
742 | bit = file_page_offset(chunk); | 744 | bit = file_page_offset(chunk); |
743 | 745 | ||
744 | /* set the bit */ | 746 | /* set the bit */ |
@@ -1322,6 +1324,18 @@ static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int n | |||
1322 | 1324 | ||
1323 | } | 1325 | } |
1324 | 1326 | ||
1327 | /* dirty the memory and file bits for bitmap chunks "s" to "e" */ | ||
1328 | void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e) | ||
1329 | { | ||
1330 | unsigned long chunk; | ||
1331 | |||
1332 | for (chunk = s; chunk <= e; chunk++) { | ||
1333 | sector_t sec = chunk << CHUNK_BLOCK_SHIFT(bitmap); | ||
1334 | bitmap_set_memory_bits(bitmap, sec, 1); | ||
1335 | bitmap_file_set_bit(bitmap, sec); | ||
1336 | } | ||
1337 | } | ||
1338 | |||
1325 | /* | 1339 | /* |
1326 | * flush out any pending updates | 1340 | * flush out any pending updates |
1327 | */ | 1341 | */ |
diff --git a/drivers/md/md.c b/drivers/md/md.c index 8b08043f07ef..b95dd8a183ec 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c | |||
@@ -2524,6 +2524,36 @@ static struct md_sysfs_entry md_new_device = | |||
2524 | __ATTR(new_dev, S_IWUSR, null_show, new_dev_store); | 2524 | __ATTR(new_dev, S_IWUSR, null_show, new_dev_store); |
2525 | 2525 | ||
2526 | static ssize_t | 2526 | static ssize_t |
2527 | bitmap_store(mddev_t *mddev, const char *buf, size_t len) | ||
2528 | { | ||
2529 | char *end; | ||
2530 | unsigned long chunk, end_chunk; | ||
2531 | |||
2532 | if (!mddev->bitmap) | ||
2533 | goto out; | ||
2534 | /* buf should be <chunk> <chunk> ... or <chunk>-<chunk> ... (range) */ | ||
2535 | while (*buf) { | ||
2536 | chunk = end_chunk = simple_strtoul(buf, &end, 0); | ||
2537 | if (buf == end) break; | ||
2538 | if (*end == '-') { /* range */ | ||
2539 | buf = end + 1; | ||
2540 | end_chunk = simple_strtoul(buf, &end, 0); | ||
2541 | if (buf == end) break; | ||
2542 | } | ||
2543 | if (*end && !isspace(*end)) break; | ||
2544 | bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk); | ||
2545 | buf = end; | ||
2546 | while (isspace(*buf)) buf++; | ||
2547 | } | ||
2548 | bitmap_unplug(mddev->bitmap); /* flush the bits to disk */ | ||
2549 | out: | ||
2550 | return len; | ||
2551 | } | ||
2552 | |||
2553 | static struct md_sysfs_entry md_bitmap = | ||
2554 | __ATTR(bitmap_set_bits, S_IWUSR, null_show, bitmap_store); | ||
2555 | |||
2556 | static ssize_t | ||
2527 | size_show(mddev_t *mddev, char *page) | 2557 | size_show(mddev_t *mddev, char *page) |
2528 | { | 2558 | { |
2529 | return sprintf(page, "%llu\n", (unsigned long long)mddev->size); | 2559 | return sprintf(page, "%llu\n", (unsigned long long)mddev->size); |
@@ -2843,6 +2873,7 @@ static struct attribute *md_redundancy_attrs[] = { | |||
2843 | &md_sync_completed.attr, | 2873 | &md_sync_completed.attr, |
2844 | &md_suspend_lo.attr, | 2874 | &md_suspend_lo.attr, |
2845 | &md_suspend_hi.attr, | 2875 | &md_suspend_hi.attr, |
2876 | &md_bitmap.attr, | ||
2846 | NULL, | 2877 | NULL, |
2847 | }; | 2878 | }; |
2848 | static struct attribute_group md_redundancy_group = { | 2879 | static struct attribute_group md_redundancy_group = { |