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/volumes.c b/fs/btrfs/volumes.c
index 5777e6a..a4e0963 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -36,6 +36,7 @@
#include "check-integrity.h"
#include "rcu-string.h"
#include "math.h"
+#include "dev-replace.h"
static int init_first_rw_device(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
@@ -505,7 +506,8 @@
return ERR_PTR(-ENOMEM);
}
-void btrfs_close_extra_devices(struct btrfs_fs_devices *fs_devices)
+void btrfs_close_extra_devices(struct btrfs_fs_info *fs_info,
+ struct btrfs_fs_devices *fs_devices, int step)
{
struct btrfs_device *device, *next;
@@ -528,6 +530,21 @@
continue;
}
+ if (device->devid == BTRFS_DEV_REPLACE_DEVID) {
+ /*
+ * In the first step, keep the device which has
+ * the correct fsid and the devid that is used
+ * for the dev_replace procedure.
+ * In the second step, the dev_replace state is
+ * read from the device tree and it is known
+ * whether the procedure is really active or
+ * not, which means whether this device is
+ * used or whether it should be removed.
+ */
+ if (step == 0 || device->is_tgtdev_for_dev_replace) {
+ continue;
+ }
+ }
if (device->bdev) {
blkdev_put(device->bdev, device->mode);
device->bdev = NULL;
@@ -536,7 +553,8 @@
if (device->writeable) {
list_del_init(&device->dev_alloc_list);
device->writeable = 0;
- fs_devices->rw_devices--;
+ if (!device->is_tgtdev_for_dev_replace)
+ fs_devices->rw_devices--;
}
list_del_init(&device->dev_list);
fs_devices->num_devices--;
@@ -594,7 +612,7 @@
if (device->bdev)
fs_devices->open_devices--;
- if (device->writeable) {
+ if (device->writeable && !device->is_tgtdev_for_dev_replace) {
list_del_init(&device->dev_alloc_list);
fs_devices->rw_devices--;
}
@@ -718,7 +736,7 @@
fs_devices->rotating = 1;
fs_devices->open_devices++;
- if (device->writeable) {
+ if (device->writeable && !device->is_tgtdev_for_dev_replace) {
fs_devices->rw_devices++;
list_add(&device->dev_alloc_list,
&fs_devices->alloc_list);
@@ -1350,16 +1368,22 @@
root->fs_info->avail_system_alloc_bits |
root->fs_info->avail_metadata_alloc_bits;
- if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) &&
- root->fs_info->fs_devices->num_devices <= 4) {
+ num_devices = root->fs_info->fs_devices->num_devices;
+ btrfs_dev_replace_lock(&root->fs_info->dev_replace);
+ if (btrfs_dev_replace_is_ongoing(&root->fs_info->dev_replace)) {
+ WARN_ON(num_devices < 1);
+ num_devices--;
+ }
+ btrfs_dev_replace_unlock(&root->fs_info->dev_replace);
+
+ if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
printk(KERN_ERR "btrfs: unable to go below four devices "
"on raid10\n");
ret = -EINVAL;
goto out;
}
- if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) &&
- root->fs_info->fs_devices->num_devices <= 2) {
+ if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
printk(KERN_ERR "btrfs: unable to go below two "
"devices on raid1\n");
ret = -EINVAL;
@@ -2935,6 +2959,7 @@
u64 allowed;
int mixed = 0;
int ret;
+ u64 num_devices;
if (btrfs_fs_closing(fs_info) ||
atomic_read(&fs_info->balance_pause_req) ||
@@ -2963,10 +2988,17 @@
}
}
+ num_devices = fs_info->fs_devices->num_devices;
+ btrfs_dev_replace_lock(&fs_info->dev_replace);
+ if (btrfs_dev_replace_is_ongoing(&fs_info->dev_replace)) {
+ BUG_ON(num_devices < 1);
+ num_devices--;
+ }
+ btrfs_dev_replace_unlock(&fs_info->dev_replace);
allowed = BTRFS_AVAIL_ALLOC_BIT_SINGLE;
- if (fs_info->fs_devices->num_devices == 1)
+ if (num_devices == 1)
allowed |= BTRFS_BLOCK_GROUP_DUP;
- else if (fs_info->fs_devices->num_devices < 4)
+ else if (num_devices < 4)
allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1);
else
allowed |= (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID1 |
@@ -3591,6 +3623,7 @@
devices_info[ndevs].total_avail = total_avail;
devices_info[ndevs].dev = device;
++ndevs;
+ WARN_ON(ndevs > fs_devices->rw_devices);
}
/*
@@ -4773,6 +4806,7 @@
device->io_align = btrfs_device_io_align(leaf, dev_item);
device->io_width = btrfs_device_io_width(leaf, dev_item);
device->sector_size = btrfs_device_sector_size(leaf, dev_item);
+ WARN_ON(device->devid == BTRFS_DEV_REPLACE_DEVID);
device->is_tgtdev_for_dev_replace = 0;
ptr = (unsigned long)btrfs_device_uuid(dev_item);