From 9e0baf60dea69f31ac3b1adeb35b03b02a53e8e1 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Fri, 15 Jul 2011 15:16:44 +0000 Subject: Btrfs: fix enospc problems with delalloc So I had this brilliant idea to use atomic counters for outstanding and reserved extents, but this turned out to be a bad idea. Consider this where we have 1 outstanding extent and 1 reserved extent Reserver Releaser atomic_dec(outstanding) now 0 atomic_read(outstanding)+1 get 1 atomic_read(reserved) get 1 don't actually reserve anything because they are the same atomic_cmpxchg(reserved, 1, 0) atomic_inc(outstanding) atomic_add(0, reserved) free reserved space for 1 extent Then the reserver now has no actual space reserved for it, and when it goes to finish the ordered IO it won't have enough space to do it's allocation and you get those lovely warnings. Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- fs/btrfs/btrfs_inode.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'fs/btrfs/btrfs_inode.h') diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index 52d7eca8c7bf..03dce3f40ce0 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -34,6 +34,9 @@ struct btrfs_inode { */ struct btrfs_key location; + /* Lock for counters */ + spinlock_t lock; + /* the extent_tree has caches of all the extent mappings to disk */ struct extent_map_tree extent_tree; @@ -134,8 +137,8 @@ struct btrfs_inode { * items we think we'll end up using, and reserved_extents is the number * of extent items we've reserved metadata for. */ - atomic_t outstanding_extents; - atomic_t reserved_extents; + unsigned outstanding_extents; + unsigned reserved_extents; /* * ordered_data_close is set by truncate when a file that used -- cgit v1.2.3 From 2cf8572dac62cc2ff7e995173e95b6c694401b3f Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 26 Jul 2011 15:35:09 -0400 Subject: Btrfs: use the commit_root for reading free_space_inode crcs Now that we are using regular file crcs for the free space cache, we can deadlock if we try to read the free_space_inode while we are updating the crc tree. This commit fixes things by using the commit_root to read the crcs. This is safe because we the free space cache file would already be loaded if that block group had been changed in the current transaction. Signed-off-by: Chris Mason --- fs/btrfs/btrfs_inode.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'fs/btrfs/btrfs_inode.h') diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index 03dce3f40ce0..502b9e988679 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -187,4 +187,13 @@ static inline void btrfs_i_size_write(struct inode *inode, u64 size) BTRFS_I(inode)->disk_i_size = size; } +static inline bool btrfs_is_free_space_inode(struct btrfs_root *root, + struct inode *inode) +{ + if (root == root->fs_info->tree_root || + BTRFS_I(inode)->location.objectid == BTRFS_FREE_INO_OBJECTID) + return true; + return false; +} + #endif -- cgit v1.2.3