summaryrefslogtreecommitdiff
path: root/fs/btrfs
diff options
context:
space:
mode:
Diffstat (limited to 'fs/btrfs')
-rw-r--r--fs/btrfs/ctree.c57
-rw-r--r--fs/btrfs/ctree.h21
-rw-r--r--fs/btrfs/extent-tree.c20
-rw-r--r--fs/btrfs/file-item.c61
-rw-r--r--fs/btrfs/super.c284
5 files changed, 394 insertions, 49 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 6b76fd967153..43d4779abdd1 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -1249,6 +1249,63 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root
return ret;
}
+int btrfs_truncate_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ u32 new_size)
+{
+ int ret = 0;
+ int slot;
+ int slot_orig;
+ struct btrfs_leaf *leaf;
+ struct buffer_head *leaf_buf;
+ u32 nritems;
+ unsigned int data_end;
+ unsigned int old_data_start;
+ unsigned int old_size;
+ unsigned int size_diff;
+ int i;
+
+ slot_orig = path->slots[0];
+ leaf_buf = path->nodes[0];
+ leaf = btrfs_buffer_leaf(leaf_buf);
+
+ nritems = btrfs_header_nritems(&leaf->header);
+ data_end = leaf_data_end(root, leaf);
+
+ slot = path->slots[0];
+ old_data_start = btrfs_item_offset(leaf->items + slot);
+ old_size = btrfs_item_size(leaf->items + slot);
+ BUG_ON(old_size <= new_size);
+ size_diff = old_size - new_size;
+
+ BUG_ON(slot < 0);
+ BUG_ON(slot >= nritems);
+
+ /*
+ * item0..itemN ... dataN.offset..dataN.size .. data0.size
+ */
+ /* first correct the data pointers */
+ for (i = slot; i < nritems; i++) {
+ u32 ioff = btrfs_item_offset(leaf->items + i);
+ btrfs_set_item_offset(leaf->items + i,
+ ioff + size_diff);
+ }
+ /* shift the data */
+printk("truncate item, new_size %u old_size %u, diff %u, bufp %p, dst, %p, num %u, old_data_start %u, data_end %u\n", new_size, old_size, size_diff, leaf, btrfs_leaf_data(leaf) + data_end + size_diff, old_data_start-data_end, old_data_start, data_end);
+ btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) +
+ data_end + size_diff, btrfs_leaf_data(leaf) +
+ data_end, old_data_start + new_size - data_end);
+ btrfs_set_item_size(leaf->items + slot, new_size);
+ btrfs_mark_buffer_dirty(leaf_buf);
+
+ ret = 0;
+ if (btrfs_leaf_free_space(root, leaf) < 0)
+ BUG();
+ check_leaf(root, path, 0);
+ return ret;
+}
+
int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_path *path, u32 data_size)
{
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 796f19d03ab5..ca3ab160f460 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -999,7 +999,7 @@ static inline void btrfs_mark_buffer_dirty(struct buffer_head *bh)
((type *)(btrfs_leaf_data(leaf) + \
btrfs_item_offset((leaf)->items + (slot))))
-/* extent-item.c */
+/* extent-tree.c */
int btrfs_inc_root_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
struct buffer_head *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
@@ -1013,9 +1013,16 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
*root, u64 blocknr, u64 num_blocks, int pin);
int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct
btrfs_root *root);
+int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 blocknr, u64 num_blocks);
/* ctree.c */
int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_path *path, u32 data_size);
+int btrfs_truncate_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ u32 new_size);
int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_key *key, struct btrfs_path *p, int
ins_len, int cow);
@@ -1073,11 +1080,10 @@ int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root
struct btrfs_key *location, int mod);
/* file-item.c */
-int btrfs_alloc_file_extent(struct btrfs_trans_handle *trans,
+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 num_blocks);
int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 objectid,
@@ -1090,6 +1096,11 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
int btrfs_csum_verify_file_block(struct btrfs_root *root,
u64 objectid, u64 offset,
char *data, size_t len);
+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);
/* super.c */
extern struct subsystem btrfs_subsys;
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index d560831c10a7..2cee9df001f6 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -12,8 +12,9 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, struct
static int del_pending_extents(struct btrfs_trans_handle *trans, struct
btrfs_root *extent_root);
-static int inc_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root
- *root, u64 blocknr, u64 num_blocks)
+int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 blocknr, u64 num_blocks)
{
struct btrfs_path *path;
int ret;
@@ -50,8 +51,9 @@ static int inc_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root
return 0;
}
-static int lookup_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root
- *root, u64 blocknr, u64 num_blocks, u32 *refs)
+static int lookup_extent_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 blocknr,
+ u64 num_blocks, u32 *refs)
{
struct btrfs_path *path;
int ret;
@@ -80,7 +82,7 @@ static int lookup_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root
int btrfs_inc_root_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
- return inc_block_ref(trans, root, bh_blocknr(root->node), 1);
+ return btrfs_inc_extent_ref(trans, root, bh_blocknr(root->node), 1);
}
int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
@@ -107,13 +109,13 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
continue;
fi = btrfs_item_ptr(buf_leaf, i,
struct btrfs_file_extent_item);
- ret = inc_block_ref(trans, root,
+ ret = btrfs_inc_extent_ref(trans, root,
btrfs_file_extent_disk_blocknr(fi),
btrfs_file_extent_disk_num_blocks(fi));
BUG_ON(ret);
} else {
blocknr = btrfs_node_blockptr(buf_node, i);
- ret = inc_block_ref(trans, root, blocknr, 1);
+ ret = btrfs_inc_extent_ref(trans, root, blocknr, 1);
BUG_ON(ret);
}
}
@@ -563,7 +565,7 @@ static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root
WARN_ON(*level < 0);
WARN_ON(*level >= BTRFS_MAX_LEVEL);
- ret = lookup_block_ref(trans, root, bh_blocknr(path->nodes[*level]),
+ ret = lookup_extent_ref(trans, root, bh_blocknr(path->nodes[*level]),
1, &refs);
BUG_ON(ret);
if (refs > 1)
@@ -587,7 +589,7 @@ static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root
}
blocknr = btrfs_node_blockptr(btrfs_buffer_node(cur),
path->slots[*level]);
- ret = lookup_block_ref(trans, root, blocknr, 1, &refs);
+ ret = lookup_extent_ref(trans, root, blocknr, 1, &refs);
BUG_ON(ret);
if (refs != 1) {
path->slots[*level]++;
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 93d42d650820..f49968ad0a07 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -6,13 +6,11 @@
#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,
+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 num_blocks)
{
- struct btrfs_key ins;
int ret = 0;
struct btrfs_file_extent_item *item;
struct btrfs_key file_key;
@@ -21,11 +19,13 @@ 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 +34,22 @@ 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, 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_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;
@@ -61,19 +62,23 @@ static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root,
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);
+printk("__lookup for %Lu\n", offset);
+ ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow);
if (ret < 0)
goto fail;
leaf = btrfs_buffer_leaf(path->nodes[0]);
if (ret > 0) {
ret = 1;
- if (path->slots[0] == 0)
+ if (path->slots[0] == 0) {
+printk("fail1\n");
goto fail;
+ }
path->slots[0]--;
btrfs_disk_key_to_cpu(&found_key,
&leaf->items[path->slots[0]].key);
if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY ||
found_key.objectid != objectid) {
+printk("fail2 type %u %Lu %Lu\n", btrfs_key_type(&found_key), found_key.objectid, objectid);
goto fail;
}
csum_offset = (offset - found_key.offset) >>
@@ -81,6 +86,7 @@ static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root,
if (csum_offset >=
btrfs_item_size(leaf->items + path->slots[0]) /
sizeof(struct btrfs_csum_item)) {
+printk("fail3, csum offset %lu size %u\n", csum_offset, btrfs_item_size(leaf->items + path->slots[0]) / sizeof(struct btrfs_csum_item));
goto fail;
}
}
@@ -89,7 +95,7 @@ static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root,
return item;
fail:
if (ret > 0)
- ret = -EIO;
+ ret = -ENOENT;
return ERR_PTR(ret);
}
@@ -105,7 +111,7 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
int cow = mod != 0;
struct btrfs_csum_item *csum_item;
- csum_item = __lookup_csum_item(root, path, objectid, offset);
+ csum_item = btrfs_lookup_csum(trans, root, path, objectid, offset, 0);
if (IS_ERR(csum_item))
return PTR_ERR(csum_item);
file_key.objectid = objectid;
@@ -113,7 +119,9 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans,
file_key.flags = 0;
btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY);
btrfs_release_path(root, path);
+printk("lookup file extent searches for %Lu\n", file_key.offset);
ret = btrfs_search_slot(trans, root, &file_key, path, ins_len, cow);
+printk("ret is %d\n", ret);
return ret;
}
@@ -134,17 +142,23 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
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);
+printk("searching for csum %Lu %Lu\n", objectid, offset);
ret = btrfs_search_slot(trans, root, &file_key, path,
sizeof(struct btrfs_csum_item), 1);
+printk("ret %d\n", ret);
if (ret < 0)
goto fail;
if (ret == 0) {
- csum_offset = 0;
- goto csum;
+ BUG();
}
if (path->slots[0] == 0) {
btrfs_release_path(root, path);
@@ -153,12 +167,15 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
path->slots[0]--;
leaf = btrfs_buffer_leaf(path->nodes[0]);
btrfs_disk_key_to_cpu(&found_key, &leaf->items[path->slots[0]].key);
+printk("found key %Lu %Lu %u\n", found_key.objectid, found_key.offset, found_key.flags);
csum_offset = (offset - found_key.offset) >>
root->fs_info->sb->s_blocksize_bits;
+printk("csum_offset %Lu\n", csum_offset);
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);
+printk("insert1\n");
goto insert;
}
if (csum_offset >= btrfs_item_size(leaf->items + path->slots[0]) /
@@ -166,11 +183,13 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
ret = btrfs_extend_item(trans, root, path,
sizeof(struct btrfs_csum_item));
BUG_ON(ret);
+printk("item extended\n");
goto csum;
}
insert:
csum_offset = 0;
+printk("inserting item %Lu %Lu %u\n", file_key.objectid, file_key.offset, file_key.flags);
ret = btrfs_insert_empty_item(trans, root, path, &file_key,
sizeof(struct btrfs_csum_item));
if (ret != 0 && ret != -EEXIST)
@@ -180,12 +199,14 @@ csum:
struct btrfs_csum_item);
ret = 0;
item += csum_offset;
+found:
ret = btrfs_csum_data(root, data, len, item->csum);
btrfs_set_csum_extent_offset(item, extent_offset);
btrfs_mark_buffer_dirty(path->nodes[0]);
fail:
btrfs_release_path(root, path);
btrfs_free_path(path);
+printk("return ret %d\n", ret);
return ret;
}
@@ -208,7 +229,7 @@ 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);
goto fail;
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index ec689992fdf4..6a56416147e6 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1089,7 +1089,6 @@ static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
extent_start = btrfs_disk_key_offset(&leaf->items[path->slots[0]].key);
extent_start = extent_start >> inode->i_blkbits;
- extent_start += btrfs_file_extent_offset(item);
extent_end = extent_start + btrfs_file_extent_num_blocks(item);
if (iblock >= extent_start && iblock < extent_end) {
err = 0;
@@ -1103,6 +1102,7 @@ allocate:
err = 0;
goto out;
}
+#if 0
ret = btrfs_alloc_file_extent(trans, root, objectid,
iblock << inode->i_blkbits,
1, extent_end, &blocknr);
@@ -1115,9 +1115,11 @@ allocate:
map_bh(result, inode->i_sb, blocknr);
btrfs_map_bh_to_logical(root, result, blocknr);
+#endif
out:
btrfs_release_path(root, path);
btrfs_free_path(path);
+printk("mapping iblock %lu to %lu\n", iblock, result->b_blocknr);
if (trans)
btrfs_end_transaction(trans, root);
return err;
@@ -1273,8 +1275,244 @@ failed:
return err;
}
-static int prepare_pages(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
+static int drop_csums(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode,
+ u64 start, u64 end)
+{
+ struct btrfs_path *path;
+ struct btrfs_leaf *leaf;
+ struct btrfs_key key;
+ int slot;
+ struct btrfs_csum_item *item;
+ char *old_block = NULL;
+ u64 cur = start;
+ u64 found_end;
+ u64 num_csums;
+ u64 item_size;
+ int ret;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ while(cur < end) {
+ item = btrfs_lookup_csum(trans, root, path,
+ inode->i_ino, cur, 1);
+ if (IS_ERR(item)) {
+ cur += root->blocksize;
+ continue;
+ }
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ slot = path->slots[0];
+ btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
+ item_size = btrfs_item_size(leaf->items + slot);
+ num_csums = item_size / sizeof(struct btrfs_csum_item);
+ found_end = key.offset + (num_csums << inode->i_blkbits);
+ cur = found_end;
+
+ if (found_end > end) {
+ char *src;
+ old_block = kmalloc(root->blocksize, GFP_NOFS);
+ src = btrfs_item_ptr(leaf, slot, char);
+ memcpy(old_block, src, item_size);
+ }
+ if (key.offset < start) {
+ u64 new_size = (start - key.offset) >>
+ inode->i_blkbits;
+ new_size *= sizeof(struct btrfs_csum_item);
+ ret = btrfs_truncate_item(trans, root, path, new_size);
+ BUG_ON(ret);
+ } else {
+ btrfs_del_item(trans, root, path);
+ }
+ btrfs_release_path(root, path);
+ if (found_end > end) {
+ char *dst;
+ int i;
+ int new_size;
+
+ num_csums = (found_end - end) >> inode->i_blkbits;
+ new_size = num_csums * sizeof(struct btrfs_csum_item);
+ key.offset = end;
+ ret = btrfs_insert_empty_item(trans, root, path,
+ &key, new_size);
+ BUG_ON(ret);
+ dst = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+ path->slots[0], char);
+ memcpy(dst, old_block + item_size - new_size,
+ new_size);
+ item = (struct btrfs_csum_item *)dst;
+ for (i = 0; i < num_csums; i++) {
+ btrfs_set_csum_extent_offset(item, end);
+ item++;
+ }
+ mark_buffer_dirty(path->nodes[0]);
+ kfree(old_block);
+ break;
+ }
+ }
+ btrfs_free_path(path);
+ return 0;
+}
+
+static int drop_extents(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode,
+ u64 start, u64 end)
+{
+ int ret;
+ struct btrfs_key key;
+ struct btrfs_leaf *leaf;
+ int slot;
+ struct btrfs_file_extent_item *extent;
+ u64 extent_end;
+ int keep;
+ struct btrfs_file_extent_item old;
+ struct btrfs_path *path;
+ u64 search_start = start;
+ int bookend;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+search_again:
+printk("drop extent inode %lu start %Lu end %Lu\n", inode->i_ino, start, end);
+ ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
+ search_start, -1);
+ if (ret != 0) {
+printk("lookup failed\n");
+ goto out;
+ }
+ while(1) {
+ keep = 0;
+ bookend = 0;
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ slot = path->slots[0];
+ btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
+
+printk("found key %Lu %Lu %u\n", key.objectid, key.offset, key.flags);
+
+ extent = btrfs_item_ptr(leaf, slot,
+ struct btrfs_file_extent_item);
+ extent_end = key.offset +
+ (btrfs_file_extent_num_blocks(extent) <<
+ inode->i_blkbits);
+printk("extent end is %Lu\n", extent_end);
+ if (key.offset >= end || key.objectid != inode->i_ino) {
+ ret = 0;
+ goto out;
+ }
+ if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
+ goto next_leaf;
+
+ if (end < extent_end && end >= key.offset) {
+ memcpy(&old, extent, sizeof(old));
+ ret = btrfs_inc_extent_ref(trans, root,
+ btrfs_file_extent_disk_blocknr(&old),
+ btrfs_file_extent_disk_num_blocks(&old));
+ BUG_ON(ret);
+ bookend = 1;
+ }
+
+ if (start > key.offset) {
+ u64 new_num;
+ /* truncate existing extent */
+ keep = 1;
+ WARN_ON(start & (root->blocksize - 1));
+ new_num = (start - key.offset) >> inode->i_blkbits;
+printk("truncating existing extent, was %Lu ", btrfs_file_extent_num_blocks(extent));
+ btrfs_set_file_extent_num_blocks(extent, new_num);
+printk("now %Lu\n", btrfs_file_extent_num_blocks(extent));
+
+ mark_buffer_dirty(path->nodes[0]);
+ }
+ if (!keep) {
+ u64 disk_blocknr;
+ u64 disk_num_blocks;
+printk("del old\n");
+ disk_blocknr = btrfs_file_extent_disk_blocknr(extent);
+ disk_num_blocks =
+ btrfs_file_extent_disk_num_blocks(extent);
+ search_start = key.offset +
+ (btrfs_file_extent_num_blocks(extent) <<
+ inode->i_blkbits);
+ ret = btrfs_del_item(trans, root, path);
+ BUG_ON(ret);
+ btrfs_release_path(root, path);
+
+ ret = btrfs_free_extent(trans, root, disk_blocknr,
+ disk_num_blocks, 0);
+
+ BUG_ON(ret);
+ if (!bookend && search_start >= end) {
+ ret = 0;
+ goto out;
+ }
+ if (!bookend)
+ goto search_again;
+ }
+ if (bookend) {
+ /* create bookend */
+ struct btrfs_key ins;
+printk("bookend! extent end %Lu\n", extent_end);
+ ins.objectid = inode->i_ino;
+ ins.offset = end;
+ ins.flags = 0;
+ btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY);
+
+ btrfs_release_path(root, path);
+ ret = drop_csums(trans, root, inode, start, end);
+ BUG_ON(ret);
+ ret = btrfs_insert_empty_item(trans, root, path, &ins,
+ sizeof(*extent));
+ BUG_ON(ret);
+ extent = btrfs_item_ptr(
+ btrfs_buffer_leaf(path->nodes[0]),
+ path->slots[0],
+ struct btrfs_file_extent_item);
+ btrfs_set_file_extent_disk_blocknr(extent,
+ btrfs_file_extent_disk_blocknr(&old));
+ btrfs_set_file_extent_disk_num_blocks(extent,
+ btrfs_file_extent_disk_num_blocks(&old));
+
+ btrfs_set_file_extent_offset(extent,
+ btrfs_file_extent_offset(&old) +
+ ((end - key.offset) >> inode->i_blkbits));
+ WARN_ON(btrfs_file_extent_num_blocks(&old) <
+ (end - key.offset) >> inode->i_blkbits);
+ btrfs_set_file_extent_num_blocks(extent,
+ btrfs_file_extent_num_blocks(&old) -
+ ((end - key.offset) >> inode->i_blkbits));
+
+ btrfs_set_file_extent_generation(extent,
+ btrfs_file_extent_generation(&old));
+printk("new bookend at offset %Lu, file_extent_offset %Lu, file_extent_num_blocks %Lu\n", end, btrfs_file_extent_offset(extent), btrfs_file_extent_num_blocks(extent));
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+ ret = 0;
+ goto out_nocsum;
+ }
+next_leaf:
+ if (slot >= btrfs_header_nritems(&leaf->header) - 1) {
+ ret = btrfs_next_leaf(root, path);
+ if (ret) {
+ ret = 0;
+ goto out;
+ }
+ } else {
+ path->slots[0]++;
+ }
+ }
+
+out:
+ ret = drop_csums(trans, root, inode, start, end);
+ BUG_ON(ret);
+
+out_nocsum:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int prepare_pages(struct btrfs_root *root,
struct file *file,
struct page **pages,
size_t num_pages,
@@ -1289,7 +1527,6 @@ static int prepare_pages(struct btrfs_trans_handle *trans,
struct inode *inode = file->f_path.dentry->d_inode;
int offset;
int err = 0;
- int ret;
int this_write;
struct buffer_head *bh;
struct buffer_head *head;
@@ -1305,18 +1542,21 @@ static int prepare_pages(struct btrfs_trans_handle *trans,
}
offset = pos & (PAGE_CACHE_SIZE -1);
this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
- if (!PageUptodate(pages[i]) &&
- (pages[i]->index == first_index ||
- pages[i]->index == last_index) && pos < isize) {
+#if 0
+ if ((pages[i]->index == first_index ||
+ pages[i]->index == last_index) && pos < isize &&
+ !PageUptodate(pages[i])) {
ret = mpage_readpage(pages[i], btrfs_get_block);
BUG_ON(ret);
lock_page(pages[i]);
}
+#endif
create_empty_buffers(pages[i], root->fs_info->sb->s_blocksize,
(1 << BH_Uptodate));
head = page_buffers(pages[i]);
bh = head;
do {
+printk("mapping page %lu to block %Lu\n", pages[i]->index, alloc_extent_start);
err = btrfs_map_bh_to_logical(root, bh,
alloc_extent_start);
BUG_ON(err);
@@ -1351,7 +1591,7 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
int ret = 0;
struct inode *inode = file->f_path.dentry->d_inode;
struct btrfs_root *root = BTRFS_I(inode)->root;
- struct page *pages[1];
+ struct page *pages[8];
unsigned long first_index;
unsigned long last_index;
u64 start_pos;
@@ -1359,6 +1599,7 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
u64 alloc_extent_start;
u64 orig_extent_start;
struct btrfs_trans_handle *trans;
+ struct btrfs_key ins;
if (file->f_flags & O_DIRECT)
return -EINVAL;
@@ -1390,16 +1631,24 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
trans = btrfs_start_transaction(root, 1);
if (!trans) {
err = -ENOMEM;
+ mutex_unlock(&root->fs_info->fs_mutex);
goto out_unlock;
}
- ret = btrfs_alloc_file_extent(trans, root, inode->i_ino,
- start_pos, num_blocks, 1,
- &alloc_extent_start);
- BUG_ON(ret);
-
+ if (start_pos < inode->i_size) {
+ ret = drop_extents(trans, root, inode,
+ start_pos,
+ (pos + count + root->blocksize -1) &
+ ~(root->blocksize - 1));
+ }
orig_extent_start = start_pos;
- ret = btrfs_end_transaction(trans, root);
+ ret = btrfs_alloc_extent(trans, root, num_blocks, 1,
+ (u64)-1, &ins);
+ BUG_ON(ret);
+ ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
+ start_pos, ins.objectid, ins.offset);
BUG_ON(ret);
+ alloc_extent_start = ins.objectid;
+ ret = btrfs_end_transaction(trans, root);
mutex_unlock(&root->fs_info->fs_mutex);
while(count > 0) {
@@ -1407,16 +1656,21 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
PAGE_CACHE_SHIFT;
- ret = prepare_pages(NULL, root, file, pages, num_pages,
+printk("num_pages is %lu\n", num_pages);
+
+ memset(pages, 0, sizeof(pages));
+ ret = prepare_pages(root, file, pages, num_pages,
pos, first_index, last_index,
write_bytes, alloc_extent_start);
BUG_ON(ret);
+
/* FIXME blocks != pagesize */
alloc_extent_start += num_pages;
ret = btrfs_copy_from_user(pos, num_pages,
write_bytes, pages, buf);
BUG_ON(ret);
+printk("2num_pages is %lu\n", num_pages);
ret = dirty_and_release_pages(NULL, root, file, pages,
num_pages, orig_extent_start,
pos, write_bytes);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-18 12:59:32 +0000