Btrfs: add better -ENOSPC handling
This is a step in the direction of better -ENOSPC handling. Instead of
checking the global bytes counter we check the space_info bytes counters to
make sure we have enough space.
If we don't we go ahead and try to allocate a new chunk, and then if that fails
we return -ENOSPC. This patch adds two counters to btrfs_space_info,
bytes_delalloc and bytes_may_use.
bytes_delalloc account for extents we've actually setup for delalloc and will
be allocated at some point down the line.
bytes_may_use is to keep track of how many bytes we may use for delalloc at
some point. When we actually set the extent_bit for the delalloc bytes we
subtract the reserved bytes from the bytes_may_use counter. This keeps us from
not actually being able to allocate space for any delalloc bytes.
Signed-off-by: Josef Bacik <jbacik@redhat.com>
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 766b31a..82491ba 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -596,13 +596,27 @@
struct btrfs_space_info {
u64 flags;
- u64 total_bytes;
- u64 bytes_used;
- u64 bytes_pinned;
- u64 bytes_reserved;
- u64 bytes_readonly;
- int full;
- int force_alloc;
+
+ u64 total_bytes; /* total bytes in the space */
+ u64 bytes_used; /* total bytes used on disk */
+ u64 bytes_pinned; /* total bytes pinned, will be freed when the
+ transaction finishes */
+ u64 bytes_reserved; /* total bytes the allocator has reserved for
+ current allocations */
+ u64 bytes_readonly; /* total bytes that are read only */
+
+ /* delalloc accounting */
+ u64 bytes_delalloc; /* number of bytes reserved for allocation,
+ this space is not necessarily reserved yet
+ by the allocator */
+ u64 bytes_may_use; /* number of bytes that may be used for
+ delalloc */
+
+ int full; /* indicates that we cannot allocate any more
+ chunks for this space */
+ int force_alloc; /* set if we need to force a chunk alloc for
+ this space */
+
struct list_head list;
/* for block groups in our same type */
@@ -1782,6 +1796,16 @@
int btrfs_cleanup_reloc_trees(struct btrfs_root *root);
int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len);
u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags);
+void btrfs_set_inode_space_info(struct btrfs_root *root, struct inode *ionde);
+int btrfs_check_metadata_free_space(struct btrfs_root *root);
+int btrfs_check_data_free_space(struct btrfs_root *root, struct inode *inode,
+ u64 bytes);
+void btrfs_free_reserved_data_space(struct btrfs_root *root,
+ struct inode *inode, u64 bytes);
+void btrfs_delalloc_reserve_space(struct btrfs_root *root, struct inode *inode,
+ u64 bytes);
+void btrfs_delalloc_free_space(struct btrfs_root *root, struct inode *inode,
+ u64 bytes);
/* ctree.c */
int btrfs_previous_item(struct btrfs_root *root,
struct btrfs_path *path, u64 min_objectid,
@@ -2027,8 +2051,6 @@
unsigned long btrfs_force_ra(struct address_space *mapping,
struct file_ra_state *ra, struct file *file,
pgoff_t offset, pgoff_t last_index);
-int btrfs_check_free_space(struct btrfs_root *root, u64 num_required,
- int for_del);
int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page);
int btrfs_readpage(struct file *file, struct page *page);
void btrfs_delete_inode(struct inode *inode);