@@ -3378,19 +3378,17 @@ struct buffer_head *btrfs_read_dev_super(struct block_device *bdev)
}
/*
- * this should be called twice, once with wait == 0 and
- * once with wait == 1. When wait == 0 is done, all the buffer heads
- * we write are pinned.
+ * Write superblock @sb to the @device. Do not wait for completion, all the
+ * buffer heads we write are pinned.
*
- * They are released when wait == 1 is done.
- * max_mirrors must be the same for both runs, and it indicates how
- * many supers on this one device should be written.
+ * Write @max_mirrors copies of the superblock, where 0 means default that fit
+ * the expected device size at commit time. Note that max_mirrors must be
+ * same for write and wait phases.
*
- * max_mirrors == 0 means to write them all.
+ * Return number of errors when buffer head is not found or submission fails.
*/
static int write_dev_supers(struct btrfs_device *device,
- struct btrfs_super_block *sb,
- int wait, int max_mirrors)
+ struct btrfs_super_block *sb, int max_mirrors)
{
struct buffer_head *bh;
int i;
@@ -3408,57 +3406,33 @@ static int write_dev_supers(struct btrfs_device *device,
device->commit_total_bytes)
break;
- if (wait) {
- bh = __find_get_block(device->bdev, bytenr / 4096,
- BTRFS_SUPER_INFO_SIZE);
- if (!bh) {
- errors++;
- continue;
- }
- wait_on_buffer(bh);
- if (!buffer_uptodate(bh))
- errors++;
+ btrfs_set_super_bytenr(sb, bytenr);
- /* drop our reference */
- brelse(bh);
+ crc = ~(u32)0;
+ crc = btrfs_csum_data((const char *)sb + BTRFS_CSUM_SIZE, crc,
+ BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE);
+ btrfs_csum_final(crc, sb->csum);
- /* drop the reference from the wait == 0 run */
- brelse(bh);
+ /* One reference for us, and we leave it for the caller */
+ bh = __getblk(device->bdev, bytenr / 4096,
+ BTRFS_SUPER_INFO_SIZE);
+ if (!bh) {
+ btrfs_err(device->fs_info,
+ "couldn't get super buffer head for bytenr %llu",
+ bytenr);
+ errors++;
continue;
- } else {
- btrfs_set_super_bytenr(sb, bytenr);
-
- crc = ~(u32)0;
- crc = btrfs_csum_data((const char *)sb +
- BTRFS_CSUM_SIZE, crc,
- BTRFS_SUPER_INFO_SIZE -
- BTRFS_CSUM_SIZE);
- btrfs_csum_final(crc, sb->csum);
-
- /*
- * one reference for us, and we leave it for the
- * caller
- */
- bh = __getblk(device->bdev, bytenr / 4096,
- BTRFS_SUPER_INFO_SIZE);
- if (!bh) {
- btrfs_err(device->fs_info,
- "couldn't get super buffer head for bytenr %llu",
- bytenr);
- errors++;
- continue;
- }
+ }
- memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
+ memcpy(bh->b_data, sb, BTRFS_SUPER_INFO_SIZE);
- /* one reference for submit_bh */
- get_bh(bh);
+ /* one reference for submit_bh */
+ get_bh(bh);
- set_buffer_uptodate(bh);
- lock_buffer(bh);
- bh->b_end_io = btrfs_end_buffer_write_sync;
- bh->b_private = device;
- }
+ set_buffer_uptodate(bh);
+ lock_buffer(bh);
+ bh->b_end_io = btrfs_end_buffer_write_sync;
+ bh->b_private = device;
/*
* we fua the first super. The others we allow
@@ -3477,6 +3451,49 @@ static int write_dev_supers(struct btrfs_device *device,
}
/*
+ * Wait for write completion of superblocks done by write_dev_supers,
+ * @max_mirrors same for write and wait phases.
+ *
+ * Return number of errors when buffer head is not found or not marked up to
+ * date.
+ */
+static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
+{
+ struct buffer_head *bh;
+ int i;
+ int errors = 0;
+ u64 bytenr;
+
+ if (max_mirrors == 0)
+ max_mirrors = BTRFS_SUPER_MIRROR_MAX;
+
+ for (i = 0; i < max_mirrors; i++) {
+ bytenr = btrfs_sb_offset(i);
+ if (bytenr + BTRFS_SUPER_INFO_SIZE >=
+ device->commit_total_bytes)
+ break;
+
+ bh = __find_get_block(device->bdev, bytenr / 4096,
+ BTRFS_SUPER_INFO_SIZE);
+ if (!bh) {
+ errors++;
+ continue;
+ }
+ wait_on_buffer(bh);
+ if (!buffer_uptodate(bh))
+ errors++;
+
+ /* drop our reference */
+ brelse(bh);
+
+ /* drop the reference from the writing run */
+ brelse(bh);
+ }
+
+ return errors < i ? 0 : -1;
+}
+
+/*
* endio for the write_dev_flush, this will wake anyone waiting
* for the barrier when it is done
*/
@@ -3737,7 +3754,7 @@ int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
flags = btrfs_super_flags(sb);
btrfs_set_super_flags(sb, flags | BTRFS_HEADER_FLAG_WRITTEN);
- ret = write_dev_supers(dev, sb, 0, max_mirrors);
+ ret = write_dev_supers(dev, sb, max_mirrors);
if (ret)
total_errors++;
}
@@ -3760,7 +3777,7 @@ int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors)
if (!dev->in_fs_metadata || !dev->writeable)
continue;
- ret = write_dev_supers(dev, sb, 1, max_mirrors);
+ ret = wait_dev_supers(dev, max_mirrors);
if (ret)
total_errors++;
}
There are two independent parts, one that writes the superblocks and another that waits for completion. No functional changes, but cleanups, reformatting and comment updates. Signed-off-by: David Sterba <dsterba@suse.com> --- fs/btrfs/disk-io.c | 129 ++++++++++++++++++++++++++++++----------------------- 1 file changed, 73 insertions(+), 56 deletions(-)