Btrfs: change core code of btrfs to support the device replace operations
This commit contains all the essential changes to the core code
of Btrfs for support of the device replace procedure.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
diff --git a/fs/btrfs/reada.c b/fs/btrfs/reada.c
index 9f363e1..c705a48 100644
--- a/fs/btrfs/reada.c
+++ b/fs/btrfs/reada.c
@@ -27,6 +27,7 @@
#include "volumes.h"
#include "disk-io.h"
#include "transaction.h"
+#include "dev-replace.h"
#undef DEBUG
@@ -331,6 +332,7 @@
int nzones = 0;
int i;
unsigned long index = logical >> PAGE_CACHE_SHIFT;
+ int dev_replace_is_ongoing;
spin_lock(&fs_info->reada_lock);
re = radix_tree_lookup(&fs_info->reada_tree, index);
@@ -392,6 +394,7 @@
}
/* insert extent in reada_tree + all per-device trees, all or nothing */
+ btrfs_dev_replace_lock(&fs_info->dev_replace);
spin_lock(&fs_info->reada_lock);
ret = radix_tree_insert(&fs_info->reada_tree, index, re);
if (ret == -EEXIST) {
@@ -399,13 +402,17 @@
BUG_ON(!re_exist);
re_exist->refcnt++;
spin_unlock(&fs_info->reada_lock);
+ btrfs_dev_replace_unlock(&fs_info->dev_replace);
goto error;
}
if (ret) {
spin_unlock(&fs_info->reada_lock);
+ btrfs_dev_replace_unlock(&fs_info->dev_replace);
goto error;
}
prev_dev = NULL;
+ dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(
+ &fs_info->dev_replace);
for (i = 0; i < nzones; ++i) {
dev = bbio->stripes[i].dev;
if (dev == prev_dev) {
@@ -422,6 +429,14 @@
/* cannot read ahead on missing device */
continue;
}
+ if (dev_replace_is_ongoing &&
+ dev == fs_info->dev_replace.tgtdev) {
+ /*
+ * as this device is selected for reading only as
+ * a last resort, skip it for read ahead.
+ */
+ continue;
+ }
prev_dev = dev;
ret = radix_tree_insert(&dev->reada_extents, index, re);
if (ret) {
@@ -434,10 +449,12 @@
BUG_ON(fs_info == NULL);
radix_tree_delete(&fs_info->reada_tree, index);
spin_unlock(&fs_info->reada_lock);
+ btrfs_dev_replace_unlock(&fs_info->dev_replace);
goto error;
}
}
spin_unlock(&fs_info->reada_lock);
+ btrfs_dev_replace_unlock(&fs_info->dev_replace);
kfree(bbio);
return re;