summaryrefslogtreecommitdiff
path: root/drivers/md/bitmap.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/md/bitmap.c')
-rw-r--r--drivers/md/bitmap.c199
1 files changed, 169 insertions, 30 deletions
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index bc552bbad83e..a35561f8f57d 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -698,7 +698,7 @@ static int bitmap_storage_alloc(struct bitmap_storage *store,
return -ENOMEM;
if (with_super && !store->sb_page) {
- store->sb_page = alloc_page(GFP_KERNEL);
+ store->sb_page = alloc_page(GFP_KERNEL|__GFP_ZERO);
if (store->sb_page == NULL)
return -ENOMEM;
store->sb_page->index = 0;
@@ -709,7 +709,7 @@ static int bitmap_storage_alloc(struct bitmap_storage *store,
pnum = 1;
}
for ( ; pnum < num_pages; pnum++) {
- store->filemap[pnum] = alloc_page(GFP_KERNEL);
+ store->filemap[pnum] = alloc_page(GFP_KERNEL|__GFP_ZERO);
if (!store->filemap[pnum]) {
store->file_pages = pnum;
return -ENOMEM;
@@ -1630,8 +1630,6 @@ int bitmap_create(struct mddev *mddev)
{
struct bitmap *bitmap;
sector_t blocks = mddev->resync_max_sectors;
- unsigned long chunks;
- unsigned long pages;
struct file *file = mddev->bitmap_info.file;
int err;
struct sysfs_dirent *bm = NULL;
@@ -1691,37 +1689,14 @@ int bitmap_create(struct mddev *mddev)
goto error;
bitmap->daemon_lastrun = jiffies;
- bitmap->counts.chunkshift = (ffz(~mddev->bitmap_info.chunksize)
- - BITMAP_BLOCK_SHIFT);
-
- chunks = DIV_ROUND_UP_SECTOR_T(blocks, 1 << bitmap->counts.chunkshift);
- pages = DIV_ROUND_UP(chunks, PAGE_COUNTER_RATIO);
-
- BUG_ON(!pages);
-
- bitmap->counts.chunks = chunks;
- bitmap->counts.pages = pages;
- bitmap->counts.missing_pages = pages;
-
- bitmap->counts.bp = kzalloc(pages * sizeof(*bitmap->counts.bp),
- GFP_KERNEL);
-
- err = -ENOMEM;
- if (!bitmap->counts.bp)
+ err = bitmap_resize(bitmap, blocks, mddev->bitmap_info.chunksize, 1);
+ if (err)
goto error;
- if (file || mddev->bitmap_info.offset) {
- err = bitmap_storage_alloc(&bitmap->storage, bitmap->counts.chunks,
- !mddev->bitmap_info.external);
- if (err)
- goto error;
- }
printk(KERN_INFO "created bitmap (%lu pages) for device %s\n",
- pages, bmname(bitmap));
+ bitmap->counts.pages, bmname(bitmap));
mddev->bitmap = bitmap;
-
-
return test_bit(BITMAP_WRITE_ERROR, &bitmap->flags) ? -EIO : 0;
error:
@@ -1807,6 +1782,170 @@ void bitmap_status(struct seq_file *seq, struct bitmap *bitmap)
seq_printf(seq, "\n");
}
+int bitmap_resize(struct bitmap *bitmap, sector_t blocks,
+ int chunksize, int init)
+{
+ /* If chunk_size is 0, choose an appropriate chunk size.
+ * Then possibly allocate new storage space.
+ * Then quiesce, copy bits, replace bitmap, and re-start
+ *
+ * This function is called both to set up the initial bitmap
+ * and to resize the bitmap while the array is active.
+ * If this happens as a result of the array being resized,
+ * chunksize will be zero, and we need to choose a suitable
+ * chunksize, otherwise we use what we are given.
+ */
+ struct bitmap_storage store;
+ struct bitmap_counts old_counts;
+ unsigned long chunks;
+ sector_t block;
+ sector_t old_blocks, new_blocks;
+ int chunkshift;
+ int ret = 0;
+ long pages;
+ struct bitmap_page *new_bp;
+
+ if (chunksize == 0) {
+ /* If there is enough space, leave the chunk size unchanged,
+ * else increase by factor of two until there is enough space.
+ */
+ long bytes;
+ long space = bitmap->mddev->bitmap_info.space;
+
+ if (space == 0) {
+ /* We don't know how much space there is, so limit
+ * to current size - in sectors.
+ */
+ bytes = DIV_ROUND_UP(bitmap->counts.chunks, 8);
+ if (!bitmap->mddev->bitmap_info.external)
+ bytes += sizeof(bitmap_super_t);
+ space = DIV_ROUND_UP(bytes, 512);
+ bitmap->mddev->bitmap_info.space = space;
+ }
+ chunkshift = bitmap->counts.chunkshift;
+ chunkshift--;
+ do {
+ /* 'chunkshift' is shift from block size to chunk size */
+ chunkshift++;
+ chunks = DIV_ROUND_UP_SECTOR_T(blocks, 1 << chunkshift);
+ bytes = DIV_ROUND_UP(chunks, 8);
+ if (!bitmap->mddev->bitmap_info.external)
+ bytes += sizeof(bitmap_super_t);
+ } while (bytes > (space << 9));
+ } else
+ chunkshift = ffz(~chunksize) - BITMAP_BLOCK_SHIFT;
+
+ chunks = DIV_ROUND_UP_SECTOR_T(blocks, 1 << chunkshift);
+ memset(&store, 0, sizeof(store));
+ if (bitmap->mddev->bitmap_info.offset || bitmap->mddev->bitmap_info.file)
+ ret = bitmap_storage_alloc(&store, chunks,
+ !bitmap->mddev->bitmap_info.external);
+ if (ret)
+ goto err;
+
+ pages = DIV_ROUND_UP(chunks, PAGE_COUNTER_RATIO);
+
+ new_bp = kzalloc(pages * sizeof(*new_bp), GFP_KERNEL);
+ ret = -ENOMEM;
+ if (!new_bp) {
+ bitmap_file_unmap(&store);
+ goto err;
+ }
+
+ if (!init)
+ bitmap->mddev->pers->quiesce(bitmap->mddev, 1);
+
+ store.file = bitmap->storage.file;
+ bitmap->storage.file = NULL;
+
+ if (store.sb_page && bitmap->storage.sb_page)
+ memcpy(page_address(store.sb_page),
+ page_address(bitmap->storage.sb_page),
+ sizeof(bitmap_super_t));
+ bitmap_file_unmap(&bitmap->storage);
+ bitmap->storage = store;
+
+ old_counts = bitmap->counts;
+ bitmap->counts.bp = new_bp;
+ bitmap->counts.pages = pages;
+ bitmap->counts.missing_pages = pages;
+ bitmap->counts.chunkshift = chunkshift;
+ bitmap->counts.chunks = chunks;
+ bitmap->mddev->bitmap_info.chunksize = 1 << (chunkshift +
+ BITMAP_BLOCK_SHIFT);
+
+ blocks = min(old_counts.chunks << old_counts.chunkshift,
+ chunks << chunkshift);
+
+ spin_lock_irq(&bitmap->counts.lock);
+ for (block = 0; block < blocks; ) {
+ bitmap_counter_t *bmc_old, *bmc_new;
+ int set;
+
+ bmc_old = bitmap_get_counter(&old_counts, block,
+ &old_blocks, 0);
+ set = bmc_old && NEEDED(*bmc_old);
+
+ if (set) {
+ bmc_new = bitmap_get_counter(&bitmap->counts, block,
+ &new_blocks, 1);
+ if (*bmc_new == 0) {
+ /* need to set on-disk bits too. */
+ sector_t end = block + new_blocks;
+ sector_t start = block >> chunkshift;
+ start <<= chunkshift;
+ while (start < end) {
+ bitmap_file_set_bit(bitmap, block);
+ start += 1 << chunkshift;
+ }
+ *bmc_new = 2;
+ bitmap_count_page(&bitmap->counts,
+ block, 1);
+ bitmap_set_pending(&bitmap->counts,
+ block);
+ }
+ *bmc_new |= NEEDED_MASK;
+ if (new_blocks < old_blocks)
+ old_blocks = new_blocks;
+ }
+ block += old_blocks;
+ }
+
+ if (!init) {
+ int i;
+ while (block < (chunks << chunkshift)) {
+ bitmap_counter_t *bmc;
+ bmc = bitmap_get_counter(&bitmap->counts, block,
+ &new_blocks, 1);
+ if (bmc) {
+ /* new space. It needs to be resynced, so
+ * we set NEEDED_MASK.
+ */
+ if (*bmc == 0) {
+ *bmc = NEEDED_MASK | 2;
+ bitmap_count_page(&bitmap->counts,
+ block, 1);
+ bitmap_set_pending(&bitmap->counts,
+ block);
+ }
+ }
+ block += new_blocks;
+ }
+ for (i = 0; i < bitmap->storage.file_pages; i++)
+ set_page_attr(bitmap, i, BITMAP_PAGE_DIRTY);
+ }
+ spin_unlock_irq(&bitmap->counts.lock);
+
+ if (!init) {
+ bitmap_unplug(bitmap);
+ bitmap->mddev->pers->quiesce(bitmap->mddev, 0);
+ }
+ ret = 0;
+err:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(bitmap_resize);
+
static ssize_t
location_show(struct mddev *mddev, char *page)
{