Btrfs: Seed device support

[safe/jmp/linux-2.6] / fs / btrfs / file-item.c

diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index f861bd5..f763788 100644 (file)
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -31,7 +31,8 @@ int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
                             struct btrfs_root *root,
                             u64 objectid, u64 pos,
                             u64 disk_offset, u64 disk_num_bytes,
-                            u64 num_bytes, u64 offset)
+                            u64 num_bytes, u64 offset, u64 ram_bytes,
+                            u8 compression, u8 encryption, u16 other_encoding)
 {
        int ret = 0;
        struct btrfs_file_extent_item *item;
@@ -57,8 +58,13 @@ int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
        btrfs_set_file_extent_disk_num_bytes(leaf, item, disk_num_bytes);
        btrfs_set_file_extent_offset(leaf, item, offset);
        btrfs_set_file_extent_num_bytes(leaf, item, num_bytes);
+       btrfs_set_file_extent_ram_bytes(leaf, item, ram_bytes);
        btrfs_set_file_extent_generation(leaf, item, trans->transid);
        btrfs_set_file_extent_type(leaf, item, BTRFS_FILE_EXTENT_REG);
+       btrfs_set_file_extent_compression(leaf, item, compression);
+       btrfs_set_file_extent_encryption(leaf, item, encryption);
+       btrfs_set_file_extent_other_encoding(leaf, item, other_encoding);
+
        btrfs_mark_buffer_dirty(leaf);
 out:
        btrfs_free_path(path);
@@ -179,6 +185,7 @@ int btrfs_lookup_bio_sums(struct btrfs_root *root, struct inode *inode,
                                       "%llu\n", inode->i_ino,
                                       (unsigned long long)offset);
                                item = NULL;
+                               btrfs_release_path(root, path);
                                goto found;
                        }
                        btrfs_item_key_to_cpu(path->nodes[0], &found_key,
@@ -213,6 +220,73 @@ found:
        return 0;
 }
 
+int btrfs_csum_file_bytes(struct btrfs_root *root, struct inode *inode,
+                         u64 start, unsigned long len)
+{
+       struct btrfs_ordered_sum *sums;
+       struct btrfs_sector_sum *sector_sum;
+       struct btrfs_ordered_extent *ordered;
+       char *data;
+       struct page *page;
+       unsigned long total_bytes = 0;
+       unsigned long this_sum_bytes = 0;
+
+       sums = kzalloc(btrfs_ordered_sum_size(root, len), GFP_NOFS);
+       if (!sums)
+               return -ENOMEM;
+
+       sector_sum = sums->sums;
+       sums->file_offset = start;
+       sums->len = len;
+       INIT_LIST_HEAD(&sums->list);
+       ordered = btrfs_lookup_ordered_extent(inode, sums->file_offset);
+       BUG_ON(!ordered);
+
+       while(len > 0) {
+               if (start >= ordered->file_offset + ordered->len ||
+                   start < ordered->file_offset) {
+                       sums->len = this_sum_bytes;
+                       this_sum_bytes = 0;
+                       btrfs_add_ordered_sum(inode, ordered, sums);
+                       btrfs_put_ordered_extent(ordered);
+
+                       sums = kzalloc(btrfs_ordered_sum_size(root, len),
+                                      GFP_NOFS);
+                       BUG_ON(!sums);
+                       sector_sum = sums->sums;
+                       sums->len = len;
+                       sums->file_offset = start;
+                       ordered = btrfs_lookup_ordered_extent(inode,
+                                                     sums->file_offset);
+                       BUG_ON(!ordered);
+               }
+
+               page = find_get_page(inode->i_mapping,
+                                    start >> PAGE_CACHE_SHIFT);
+
+               data = kmap_atomic(page, KM_USER0);
+               sector_sum->sum = ~(u32)0;
+               sector_sum->sum = btrfs_csum_data(root, data, sector_sum->sum,
+                                                 PAGE_CACHE_SIZE);
+               kunmap_atomic(data, KM_USER0);
+               btrfs_csum_final(sector_sum->sum,
+                                (char *)&sector_sum->sum);
+               sector_sum->offset = page_offset(page);
+               page_cache_release(page);
+
+               sector_sum++;
+               total_bytes += PAGE_CACHE_SIZE;
+               this_sum_bytes += PAGE_CACHE_SIZE;
+               start += PAGE_CACHE_SIZE;
+
+               WARN_ON(len < PAGE_CACHE_SIZE);
+               len -= PAGE_CACHE_SIZE;
+       }
+       btrfs_add_ordered_sum(inode, ordered, sums);
+       btrfs_put_ordered_extent(ordered);
+       return 0;
+}
+
 int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode,
                       struct bio *bio)
 {
@@ -325,6 +399,7 @@ again:
        item = btrfs_lookup_csum(trans, root, path, objectid, offset, 1);
        if (!IS_ERR(item)) {
                leaf = path->nodes[0];
+               ret = 0;
                goto found;
        }
        ret = PTR_ERR(item);