1 files changed, 39 insertions, 11 deletions

diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 3ebbc058d082..3f0e71b0e5d9 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -16,6 +16,9 @@
  * Boston, MA 021110-1307, USA.
  */
 
+#include <linux/bio.h>
+#include <linux/pagemap.h>
+#include <linux/highmem.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
@@ -131,28 +134,35 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
         return ret;
 }
 
-int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
-                          struct btrfs_root *root,
-                          struct inode *inode,
-                          u64 objectid, u64 offset,
-                          char *data, size_t len)
+int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans,
+                           struct btrfs_root *root, struct inode *inode,
+                           struct bio *bio)
 {
+        u64 objectid = inode->i_ino;
+        u64 offset;
         int ret;
         struct btrfs_key file_key;
         struct btrfs_key found_key;
-        u64 next_offset = (u64)-1;
-        int found_next = 0;
+        u64 next_offset;
+        int found_next;
         struct btrfs_path *path;
         struct btrfs_csum_item *item;
+        struct btrfs_csum_item *item_end;
         struct extent_buffer *leaf = NULL;
         u64 csum_offset;
-        u32 csum_result = ~(u32)0;
+        u32 csum_result;
         u32 nritems;
         u32 ins_size;
+        int bio_index = 0;
+        struct bio_vec *bvec = bio->bi_io_vec;
+        char *data;
 
         path = btrfs_alloc_path();
         BUG_ON(!path);
-
+again:
+        next_offset = (u64)-1;
+        found_next = 0;
+        offset = page_offset(bvec->bv_page) + bvec->bv_offset;
         file_key.objectid = objectid;
         file_key.offset = offset;
         btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
@@ -259,7 +269,15 @@ csum:
         item = (struct btrfs_csum_item *)((unsigned char *)item +
                                           csum_offset * BTRFS_CRC32_SIZE);
 found:
-        csum_result = btrfs_csum_data(root, data, csum_result, len);
+        item_end = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
+        item_end = (struct btrfs_csum_item *)((unsigned char *)item_end +
+                                      btrfs_item_size_nr(leaf, path->slots[0]));
+next_bvec:
+        data = kmap_atomic(bvec->bv_page, KM_IRQ0);
+        csum_result = ~(u32)0;
+        csum_result = btrfs_csum_data(root, data + bvec->bv_offset,
+                                      csum_result, bvec->bv_len);
+        kunmap_atomic(data, KM_IRQ0);
         btrfs_csum_final(csum_result, (char *)&csum_result);
         if (csum_result == 0) {
                 printk("csum result is 0 for inode %lu offset %Lu\n", inode->i_ino, offset);
@@ -267,9 +285,19 @@ found:
 
         write_extent_buffer(leaf, &csum_result, (unsigned long)item,
                             BTRFS_CRC32_SIZE);
+        bio_index++;
+        bvec++;
+        if (bio_index < bio->bi_vcnt) {
+                item = (struct btrfs_csum_item *)((char *)item + BTRFS_CRC32_SIZE);
+                if (item < item_end)
+                        goto next_bvec;
+        }
         btrfs_mark_buffer_dirty(path->nodes[0]);
+        if (bio_index < bio->bi_vcnt) {
+                btrfs_release_path(root, path);
+                goto again;
+        }
 fail:
-        btrfs_release_path(root, path);
         btrfs_free_path(path);
         return ret;
 }