From 36523e95129c0e69bf1592cd009261b1c6d96e77 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Fri, 7 Feb 2014 14:34:12 +0100 Subject: [PATCH] btrfs: export global block reserve size as space_info Introduce a block group type bit for a global reserve and fill the space info for SPACE_INFO ioctl. This should replace the newly added ioctl (01e219e8069516cdb98594d417b8bb8d906ed30d) to get just the 'size' part of the global reserve, while the actual usage can be now visible in the 'btrfs fi df' output during ENOSPC stress. The unpatched userspace tools will show the blockgroup as 'unknown'. CC: Jeff Mahoney CC: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Chris Mason --- fs/btrfs/ctree.h | 9 ++++++++- fs/btrfs/ioctl.c | 20 ++++++++++++++++++++ 2 files changed, 28 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index d8a669e..ad1a594 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -987,7 +987,8 @@ struct btrfs_dev_replace_item { #define BTRFS_BLOCK_GROUP_RAID10 (1ULL << 6) #define BTRFS_BLOCK_GROUP_RAID5 (1ULL << 7) #define BTRFS_BLOCK_GROUP_RAID6 (1ULL << 8) -#define BTRFS_BLOCK_GROUP_RESERVED BTRFS_AVAIL_ALLOC_BIT_SINGLE +#define BTRFS_BLOCK_GROUP_RESERVED (BTRFS_AVAIL_ALLOC_BIT_SINGLE | \ + BTRFS_SPACE_INFO_GLOBAL_RSV) enum btrfs_raid_types { BTRFS_RAID_RAID10, @@ -1019,6 +1020,12 @@ enum btrfs_raid_types { */ #define BTRFS_AVAIL_ALLOC_BIT_SINGLE (1ULL << 48) +/* + * A fake block group type that is used to communicate global block reserve + * size to userspace via the SPACE_INFO ioctl. + */ +#define BTRFS_SPACE_INFO_GLOBAL_RSV (1ULL << 49) + #define BTRFS_EXTENDED_PROFILE_MASK (BTRFS_BLOCK_GROUP_PROFILE_MASK | \ BTRFS_AVAIL_ALLOC_BIT_SINGLE) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 89d5db7..f2e8fcc 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3562,6 +3562,11 @@ static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) up_read(&info->groups_sem); } + /* + * Global block reserve, exported as a space_info + */ + slot_count++; + /* space_slots == 0 means they are asking for a count */ if (space_args.space_slots == 0) { space_args.total_spaces = slot_count; @@ -3620,6 +3625,21 @@ static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg) up_read(&info->groups_sem); } + /* + * Add global block reserve + */ + if (slot_count) { + struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv; + + spin_lock(&block_rsv->lock); + space.total_bytes = block_rsv->size; + space.used_bytes = block_rsv->size - block_rsv->reserved; + spin_unlock(&block_rsv->lock); + space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV; + memcpy(dest, &space, sizeof(space)); + space_args.total_spaces++; + } + user_dest = (struct btrfs_ioctl_space_info __user *) (arg + sizeof(struct btrfs_ioctl_space_args)); -- 2.7.4