diff mbox

[11/15] btrfs: pass number of devices to btrfs_check_raid_min_devices

Message ID 83c7c8cf473c48f6dd8eaccb2d80fcc84cf8919e.1455556900.git.dsterba@suse.com (mailing list archive)
State Accepted
Headers show

Commit Message

David Sterba Feb. 15, 2016, 5:34 p.m. UTC
Before this patch, btrfs_check_raid_min_devices would do an off-by-one
check of the constraints and not the miminmum check, as its name
suggests. This is not a problem if the only caller is device remove, but
would be confusing for others.

Add an argument with the exact number and let the caller(s) decide if
this needs any adjustments, like when device replace is running.

Signed-off-by: David Sterba <dsterba@suse.com>
---
 fs/btrfs/volumes.c | 35 ++++++++++++++++++++---------------
 1 file changed, 20 insertions(+), 15 deletions(-)

Comments

Anand Jain Feb. 16, 2016, 9:08 a.m. UTC | #1
looks good.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Tested-by: Anand Jain <anand.jain@oracle.com>

Thanks.

On 02/16/2016 01:34 AM, David Sterba wrote:
> Before this patch, btrfs_check_raid_min_devices would do an off-by-one
> check of the constraints and not the miminmum check, as its name
> suggests. This is not a problem if the only caller is device remove, but
> would be confusing for others.
>
> Add an argument with the exact number and let the caller(s) decide if
> this needs any adjustments, like when device replace is running.
>
> Signed-off-by: David Sterba <dsterba@suse.com>
> ---
>   fs/btrfs/volumes.c | 35 ++++++++++++++++++++---------------
>   1 file changed, 20 insertions(+), 15 deletions(-)
>
> diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
> index 4fa4a836a072..ae94e06f3e61 100644
> --- a/fs/btrfs/volumes.c
> +++ b/fs/btrfs/volumes.c
> @@ -1705,20 +1705,17 @@ static int btrfs_rm_dev_item(struct btrfs_root *root,
>   	return ret;
>   }
>
> -static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info)
> +/*
> + * Verify that @num_devices satisfies the RAID profile constraints in the whole
> + * filesystem. It's up to the caller to adjust that number regarding eg. device
> + * replace.
> + */
> +static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info,
> +		u64 num_devices)
>   {
>   	u64 all_avail;
> -	u64 num_devices;
>   	unsigned seq;
>
> -	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)) {
> -		WARN_ON(num_devices < 1);
> -		num_devices--;
> -	}
> -	btrfs_dev_replace_unlock(&fs_info->dev_replace);
> -
>   	do {
>   		seq = read_seqbegin(&fs_info->profiles_lock);
>
> @@ -1727,21 +1724,21 @@ static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info)
>   			    fs_info->avail_metadata_alloc_bits;
>   	} while (read_seqretry(&fs_info->profiles_lock, seq));
>
> -	if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
> +	if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices < 4) {
>   		return BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET;
>   	}
>
> -	if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
> +	if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices < 2) {
>   		return BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET;
>   	}
>
>   	if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
> -	    fs_info->fs_devices->rw_devices <= 2) {
> +	    fs_info->fs_devices->rw_devices < 2) {
>   		return BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET;
>   	}
>
>   	if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
> -	    fs_info->fs_devices->rw_devices <= 3) {
> +	    fs_info->fs_devices->rw_devices < 3) {
>   		return BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET;
>   	}
>
> @@ -1760,7 +1757,15 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path, u64 devid)
>
>   	mutex_lock(&uuid_mutex);
>
> -	ret = btrfs_check_raid_min_devices(root->fs_info);
> +	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);
> +
> +	ret = btrfs_check_raid_min_devices(root->fs_info, num_devices - 1);
>   	if (ret)
>   		goto out;
>
>
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diff mbox

Patch

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 4fa4a836a072..ae94e06f3e61 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1705,20 +1705,17 @@  static int btrfs_rm_dev_item(struct btrfs_root *root,
 	return ret;
 }
 
-static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info)
+/*
+ * Verify that @num_devices satisfies the RAID profile constraints in the whole
+ * filesystem. It's up to the caller to adjust that number regarding eg. device
+ * replace.
+ */
+static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info,
+		u64 num_devices)
 {
 	u64 all_avail;
-	u64 num_devices;
 	unsigned seq;
 
-	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)) {
-		WARN_ON(num_devices < 1);
-		num_devices--;
-	}
-	btrfs_dev_replace_unlock(&fs_info->dev_replace);
-
 	do {
 		seq = read_seqbegin(&fs_info->profiles_lock);
 
@@ -1727,21 +1724,21 @@  static int btrfs_check_raid_min_devices(struct btrfs_fs_info *fs_info)
 			    fs_info->avail_metadata_alloc_bits;
 	} while (read_seqretry(&fs_info->profiles_lock, seq));
 
-	if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices <= 4) {
+	if ((all_avail & BTRFS_BLOCK_GROUP_RAID10) && num_devices < 4) {
 		return BTRFS_ERROR_DEV_RAID10_MIN_NOT_MET;
 	}
 
-	if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices <= 2) {
+	if ((all_avail & BTRFS_BLOCK_GROUP_RAID1) && num_devices < 2) {
 		return BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET;
 	}
 
 	if ((all_avail & BTRFS_BLOCK_GROUP_RAID5) &&
-	    fs_info->fs_devices->rw_devices <= 2) {
+	    fs_info->fs_devices->rw_devices < 2) {
 		return BTRFS_ERROR_DEV_RAID5_MIN_NOT_MET;
 	}
 
 	if ((all_avail & BTRFS_BLOCK_GROUP_RAID6) &&
-	    fs_info->fs_devices->rw_devices <= 3) {
+	    fs_info->fs_devices->rw_devices < 3) {
 		return BTRFS_ERROR_DEV_RAID6_MIN_NOT_MET;
 	}
 
@@ -1760,7 +1757,15 @@  int btrfs_rm_device(struct btrfs_root *root, char *device_path, u64 devid)
 
 	mutex_lock(&uuid_mutex);
 
-	ret = btrfs_check_raid_min_devices(root->fs_info);
+	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);
+
+	ret = btrfs_check_raid_min_devices(root->fs_info, num_devices - 1);
 	if (ret)
 		goto out;