]> git.karo-electronics.de Git - mv-sheeva.git/blobdiff - fs/btrfs/file-item.c
Btrfs: printk fixes
[mv-sheeva.git] / fs / btrfs / file-item.c
index 93d42d650820d6bcfb805c5365db4d9b756130d8..d5a98827e38aca1ed219a1b2dceb2b8ade74209a 100644 (file)
@@ -2,17 +2,17 @@
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
+#include "print-tree.h"
 
 #define MAX_CSUM_ITEMS(r) ((((BTRFS_LEAF_DATA_SIZE(r) - \
-                                sizeof(struct btrfs_item)) / \
-                               sizeof(struct btrfs_csum_item)) - 1))
-int btrfs_alloc_file_extent(struct btrfs_trans_handle *trans,
+                              sizeof(struct btrfs_item) * 2) / \
+                              BTRFS_CRC32_SIZE) - 1))
+int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
                               struct btrfs_root *root,
-                              u64 objectid, u64 offset,
-                              u64 num_blocks, u64 hint_block,
-                              u64 *result)
+                              u64 objectid, u64 pos,
+                              u64 offset, u64 disk_num_blocks,
+                              u64 num_blocks)
 {
-       struct btrfs_key ins;
        int ret = 0;
        struct btrfs_file_extent_item *item;
        struct btrfs_key file_key;
@@ -21,11 +21,8 @@ int btrfs_alloc_file_extent(struct btrfs_trans_handle *trans,
        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 = offset;
+       file_key.offset = pos;
        file_key.flags = 0;
        btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
 
@@ -34,21 +31,24 @@ int btrfs_alloc_file_extent(struct btrfs_trans_handle *trans,
        BUG_ON(ret);
        item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
                              struct btrfs_file_extent_item);
-       btrfs_set_file_extent_disk_blocknr(item, ins.objectid);
-       btrfs_set_file_extent_disk_num_blocks(item, ins.offset);
+       btrfs_set_file_extent_disk_blocknr(item, offset);
+       btrfs_set_file_extent_disk_num_blocks(item, disk_num_blocks);
        btrfs_set_file_extent_offset(item, 0);
-       btrfs_set_file_extent_num_blocks(item, ins.offset);
+       btrfs_set_file_extent_num_blocks(item, num_blocks);
        btrfs_set_file_extent_generation(item, trans->transid);
+       btrfs_set_file_extent_type(item, BTRFS_FILE_EXTENT_REG);
        btrfs_mark_buffer_dirty(path->nodes[0]);
-       *result = ins.objectid;
+
        btrfs_release_path(root, path);
        btrfs_free_path(path);
        return 0;
 }
 
-static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root,
-                                                 struct btrfs_path *path,
-                                                 u64 objectid, u64 offset)
+struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans,
+                                         struct btrfs_root *root,
+                                         struct btrfs_path *path,
+                                         u64 objectid, u64 offset,
+                                         int cow)
 {
        int ret;
        struct btrfs_key file_key;
@@ -56,12 +56,13 @@ static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root,
        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;
        file_key.flags = 0;
        btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
-       ret = btrfs_search_slot(NULL, root, &file_key, path, 0, 0);
+       ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
        if (ret < 0)
                goto fail;
        leaf = btrfs_buffer_leaf(path->nodes[0]);
@@ -78,18 +79,21 @@ static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root,
                }
                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 /= BTRFS_CRC32_SIZE;
+
+               if (csum_offset >= csums_in_item) {
+                       ret = -EFBIG;
                        goto fail;
                }
        }
        item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item);
-       item += csum_offset;
+       item = (struct btrfs_csum_item *)((unsigned char *)item +
+                                         csum_offset * BTRFS_CRC32_SIZE);
        return item;
 fail:
        if (ret > 0)
-               ret = -EIO;
+               ret = -ENOENT;
        return ERR_PTR(ret);
 }
 
@@ -103,16 +107,11 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
        struct btrfs_key file_key;
        int ins_len = mod < 0 ? -1 : 0;
        int cow = mod != 0;
-       struct btrfs_csum_item *csum_item;
 
-       csum_item = __lookup_csum_item(root, path, objectid, offset);
-       if (IS_ERR(csum_item))
-               return PTR_ERR(csum_item);
        file_key.objectid = objectid;
-       file_key.offset = btrfs_csum_extent_offset(csum_item);
+       file_key.offset = offset;
        file_key.flags = 0;
        btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
-       btrfs_release_path(root, path);
        ret = btrfs_search_slot(trans, root, &file_key, path, ins_len, cow);
        return ret;
 }
@@ -120,7 +119,6 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
 int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
                          struct btrfs_root *root,
                          u64 objectid, u64 offset,
-                         u64 extent_offset,
                          char *data, size_t len)
 {
        int ret;
@@ -133,21 +131,43 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
 
        path = btrfs_alloc_path();
        BUG_ON(!path);
-       btrfs_init_path(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 / BTRFS_CRC32_SIZE) >= 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);
+                               BTRFS_CRC32_SIZE, 1);
        if (ret < 0)
                goto fail;
        if (ret == 0) {
-               csum_offset = 0;
-               goto csum;
+               BUG();
        }
        if (path->slots[0] == 0) {
-               btrfs_release_path(root, path);
                goto insert;
        }
        path->slots[0]--;
@@ -158,30 +178,39 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
        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);
                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));
+           BTRFS_CRC32_SIZE) {
+               u32 diff = (csum_offset + 1) * BTRFS_CRC32_SIZE;
+               diff = diff - btrfs_item_size(leaf->items + path->slots[0]);
+               if (diff != BTRFS_CRC32_SIZE)
+                       goto insert;
+               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)
+                                     BTRFS_CRC32_SIZE);
+       if (ret != 0) {
+               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;
-       ret = btrfs_csum_data(root, data, len, item->csum);
-       btrfs_set_csum_extent_offset(item, extent_offset);
+       item = (struct btrfs_csum_item *)((unsigned char *)item +
+                                         csum_offset * BTRFS_CRC32_SIZE);
+found:
+       btrfs_check_bounds(&item->csum, BTRFS_CRC32_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:
        btrfs_release_path(root, path);
@@ -189,6 +218,32 @@ fail:
        return ret;
 }
 
+int btrfs_csum_truncate(struct btrfs_trans_handle *trans,
+                       struct btrfs_root *root, struct btrfs_path *path,
+                       u64 isize)
+{
+       struct btrfs_key key;
+       struct btrfs_leaf *leaf = btrfs_buffer_leaf(path->nodes[0]);
+       int slot = path->slots[0];
+       int ret;
+       u32 new_item_size;
+       u64 new_item_span;
+       u64 blocks;
+
+       btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
+       if (isize <= key.offset)
+               return 0;
+       new_item_span = isize - key.offset;
+       blocks = (new_item_span + root->blocksize - 1) >>
+               root->fs_info->sb->s_blocksize_bits;
+       new_item_size = blocks * BTRFS_CRC32_SIZE;
+       if (new_item_size >= btrfs_item_size(leaf->items + slot))
+               return 0;
+       ret = btrfs_truncate_item(trans, root, path, new_item_size);
+       BUG_ON(ret);
+       return ret;
+}
+
 int btrfs_csum_verify_file_block(struct btrfs_root *root,
                                 u64 objectid, u64 offset,
                                 char *data, size_t len)
@@ -197,7 +252,7 @@ int btrfs_csum_verify_file_block(struct btrfs_root *root,
        struct btrfs_key file_key;
        struct btrfs_path *path;
        struct btrfs_csum_item *item;
-       char result[BTRFS_CSUM_SIZE];
+       char result[BTRFS_CRC32_SIZE];
 
        path = btrfs_alloc_path();
        BUG_ON(!path);
@@ -208,15 +263,18 @@ int btrfs_csum_verify_file_block(struct btrfs_root *root,
        btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY);
        mutex_lock(&root->fs_info->fs_mutex);
 
-       item = __lookup_csum_item(root, path, objectid, offset);
+       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 = -ENOENT;
                goto fail;
        }
 
        ret = btrfs_csum_data(root, data, len, result);
        WARN_ON(ret);
-       if (memcmp(result, item->csum, BTRFS_CSUM_SIZE))
+       if (memcmp(result, &item->csum, BTRFS_CRC32_SIZE))
                ret = 1;
 fail:
        btrfs_release_path(root, path);