Btrfs: working file_write, reorganized key flags
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index ff8f333..8cc3c1d 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -4,7 +4,7 @@
#include "transaction.h"
#define MAX_CSUM_ITEMS(r) ((((BTRFS_LEAF_DATA_SIZE(r) - \
- sizeof(struct btrfs_item)) / \
+ sizeof(struct btrfs_item) * 2) / \
sizeof(struct btrfs_csum_item)) - 1))
int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
@@ -19,11 +19,6 @@
path = btrfs_alloc_path();
BUG_ON(!path);
btrfs_init_path(path);
- /*
- ret = btrfs_alloc_extent(trans, root, num_blocks, hint_block,
- (u64)-1, &ins);
- */
- BUG_ON(ret);
file_key.objectid = objectid;
file_key.offset = pos;
file_key.flags = 0;
@@ -40,6 +35,7 @@
btrfs_set_file_extent_num_blocks(item, num_blocks);
btrfs_set_file_extent_generation(item, trans->transid);
btrfs_mark_buffer_dirty(path->nodes[0]);
+
btrfs_release_path(root, path);
btrfs_free_path(path);
return 0;
@@ -57,6 +53,7 @@
struct btrfs_csum_item *item;
struct btrfs_leaf *leaf;
u64 csum_offset = 0;
+ int csums_in_item;
file_key.objectid = objectid;
file_key.offset = offset;
@@ -79,9 +76,11 @@
}
csum_offset = (offset - found_key.offset) >>
root->fs_info->sb->s_blocksize_bits;
- if (csum_offset >=
- btrfs_item_size(leaf->items + path->slots[0]) /
- sizeof(struct btrfs_csum_item)) {
+ csums_in_item = btrfs_item_size(leaf->items + path->slots[0]);
+ csums_in_item /= sizeof(struct btrfs_csum_item);
+
+ if (csum_offset >= csums_in_item) {
+ ret = -EFBIG;
goto fail;
}
}
@@ -128,16 +127,36 @@
path = btrfs_alloc_path();
BUG_ON(!path);
- btrfs_init_path(path);
- item = btrfs_lookup_csum(trans, root, path, objectid, offset, 0);
- if (!IS_ERR(item))
- goto found;
- btrfs_release_path(root, path);
file_key.objectid = objectid;
file_key.offset = offset;
file_key.flags = 0;
btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
+
+ item = btrfs_lookup_csum(trans, root, path, objectid, offset, 1);
+ if (!IS_ERR(item))
+ goto found;
+ ret = PTR_ERR(item);
+ if (ret == -EFBIG) {
+ u32 item_size;
+ /* we found one, but it isn't big enough yet */
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ item_size = btrfs_item_size(leaf->items + path->slots[0]);
+ if ((item_size / sizeof(struct btrfs_csum_item)) >=
+ MAX_CSUM_ITEMS(root)) {
+ /* already at max size, make a new one */
+ goto insert;
+ }
+ } else {
+ /* we didn't find a csum item, insert one */
+ goto insert;
+ }
+
+ /*
+ * at this point, we know the tree has an item, but it isn't big
+ * enough yet to put our csum in. Grow it
+ */
+ btrfs_release_path(root, path);
ret = btrfs_search_slot(trans, root, &file_key, path,
sizeof(struct btrfs_csum_item), 1);
if (ret < 0)
@@ -146,7 +165,6 @@
BUG();
}
if (path->slots[0] == 0) {
- btrfs_release_path(root, path);
goto insert;
}
path->slots[0]--;
@@ -157,29 +175,36 @@
if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY ||
found_key.objectid != objectid ||
csum_offset >= MAX_CSUM_ITEMS(root)) {
- btrfs_release_path(root, path);
+ WARN_ON(1);
goto insert;
}
if (csum_offset >= btrfs_item_size(leaf->items + path->slots[0]) /
sizeof(struct btrfs_csum_item)) {
- ret = btrfs_extend_item(trans, root, path,
- sizeof(struct btrfs_csum_item));
+ u32 diff = (csum_offset + 1) * sizeof(struct btrfs_csum_item);
+ diff = diff - btrfs_item_size(leaf->items + path->slots[0]);
+ WARN_ON(diff != sizeof(struct btrfs_csum_item));
+ ret = btrfs_extend_item(trans, root, path, diff);
BUG_ON(ret);
goto csum;
}
insert:
+ btrfs_release_path(root, path);
csum_offset = 0;
ret = btrfs_insert_empty_item(trans, root, path, &file_key,
sizeof(struct btrfs_csum_item));
- if (ret != 0 && ret != -EEXIST)
+ if (ret != 0) {
+ printk("at insert for %Lu %u %Lu ret is %d\n", file_key.objectid, file_key.flags, file_key.offset, ret);
+ WARN_ON(1);
goto fail;
+ }
csum:
item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
struct btrfs_csum_item);
ret = 0;
item += csum_offset;
found:
+ btrfs_check_bounds(item->csum, BTRFS_CSUM_SIZE, path->nodes[0]->b_data, root->fs_info->sb->s_blocksize);
ret = btrfs_csum_data(root, data, len, item->csum);
btrfs_mark_buffer_dirty(path->nodes[0]);
fail:
@@ -210,6 +235,9 @@
item = btrfs_lookup_csum(NULL, root, path, objectid, offset, 0);
if (IS_ERR(item)) {
ret = PTR_ERR(item);
+ /* a csum that isn't present is a preallocated region. */
+ if (ret == -ENOENT || ret == -EFBIG)
+ ret = 1;
goto fail;
}