dm thin: refactor data dev resize
Refactor device size functions in preparation for similar metadata
device resizing functions.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 004ad165..111c148 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -922,7 +922,7 @@
return r;
if (free_blocks <= pool->low_water_blocks && !pool->low_water_triggered) {
- DMWARN("%s: reached low water mark, sending event.",
+ DMWARN("%s: reached low water mark for data device: sending event.",
dm_device_name(pool->pool_md));
spin_lock_irqsave(&pool->lock, flags);
pool->low_water_triggered = 1;
@@ -1909,6 +1909,20 @@
return r;
}
+static sector_t get_metadata_dev_size(struct block_device *bdev)
+{
+ sector_t metadata_dev_size = i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
+ char buffer[BDEVNAME_SIZE];
+
+ if (metadata_dev_size > THIN_METADATA_MAX_SECTORS_WARNING) {
+ DMWARN("Metadata device %s is larger than %u sectors: excess space will not be used.",
+ bdevname(bdev, buffer), THIN_METADATA_MAX_SECTORS);
+ metadata_dev_size = THIN_METADATA_MAX_SECTORS_WARNING;
+ }
+
+ return metadata_dev_size;
+}
+
/*
* thin-pool <metadata dev> <data dev>
* <data block size (sectors)>
@@ -1931,8 +1945,6 @@
unsigned long block_size;
dm_block_t low_water_blocks;
struct dm_dev *metadata_dev;
- sector_t metadata_dev_size;
- char b[BDEVNAME_SIZE];
/*
* FIXME Remove validation from scope of lock.
@@ -1953,10 +1965,11 @@
goto out_unlock;
}
- metadata_dev_size = i_size_read(metadata_dev->bdev->bd_inode) >> SECTOR_SHIFT;
- if (metadata_dev_size > THIN_METADATA_MAX_SECTORS_WARNING)
- DMWARN("Metadata device %s is larger than %u sectors: excess space will not be used.",
- bdevname(metadata_dev->bdev, b), THIN_METADATA_MAX_SECTORS);
+ /*
+ * Run for the side-effect of possibly issuing a warning if the
+ * device is too big.
+ */
+ (void) get_metadata_dev_size(metadata_dev->bdev);
r = dm_get_device(ti, argv[1], FMODE_READ | FMODE_WRITE, &data_dev);
if (r) {
@@ -2079,6 +2092,43 @@
return r;
}
+static int maybe_resize_data_dev(struct dm_target *ti, bool *need_commit)
+{
+ int r;
+ struct pool_c *pt = ti->private;
+ struct pool *pool = pt->pool;
+ sector_t data_size = ti->len;
+ dm_block_t sb_data_size;
+
+ *need_commit = false;
+
+ (void) sector_div(data_size, pool->sectors_per_block);
+
+ r = dm_pool_get_data_dev_size(pool->pmd, &sb_data_size);
+ if (r) {
+ DMERR("failed to retrieve data device size");
+ return r;
+ }
+
+ if (data_size < sb_data_size) {
+ DMERR("pool target (%llu blocks) too small: expected %llu",
+ (unsigned long long)data_size, sb_data_size);
+ return -EINVAL;
+
+ } else if (data_size > sb_data_size) {
+ r = dm_pool_resize_data_dev(pool->pmd, data_size);
+ if (r) {
+ DMERR("failed to resize data device");
+ set_pool_mode(pool, PM_READ_ONLY);
+ return r;
+ }
+
+ *need_commit = true;
+ }
+
+ return 0;
+}
+
/*
* Retrieves the number of blocks of the data device from
* the superblock and compares it to the actual device size,
@@ -2093,10 +2143,9 @@
static int pool_preresume(struct dm_target *ti)
{
int r;
+ bool need_commit1;
struct pool_c *pt = ti->private;
struct pool *pool = pt->pool;
- sector_t data_size = ti->len;
- dm_block_t sb_data_size;
/*
* Take control of the pool object.
@@ -2105,30 +2154,12 @@
if (r)
return r;
- (void) sector_div(data_size, pool->sectors_per_block);
-
- r = dm_pool_get_data_dev_size(pool->pmd, &sb_data_size);
- if (r) {
- DMERR("failed to retrieve data device size");
+ r = maybe_resize_data_dev(ti, &need_commit1);
+ if (r)
return r;
- }
- if (data_size < sb_data_size) {
- DMERR("pool target too small, is %llu blocks (expected %llu)",
- (unsigned long long)data_size, sb_data_size);
- return -EINVAL;
-
- } else if (data_size > sb_data_size) {
- r = dm_pool_resize_data_dev(pool->pmd, data_size);
- if (r) {
- DMERR("failed to resize data device");
- /* FIXME Stricter than necessary: Rollback transaction instead here */
- set_pool_mode(pool, PM_READ_ONLY);
- return r;
- }
-
+ if (need_commit1)
(void) commit_or_fallback(pool);
- }
return 0;
}