UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

Btrfs: progress on file_write 

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason 2007-04-17 13:26:50 -04:00 committed by David Woodhouse
parent 6567e837df
commit b18c668581
5 changed files with 394 additions and 49 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

57
fs/btrfs/ctree.c
View File

@ -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)
{

21
fs/btrfs/ctree.h
View File

@ -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;

20
fs/btrfs/extent-tree.c
View File

@ -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]++;

61
fs/btrfs/file-item.c
View File

@ -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;

284
fs/btrfs/super.c
View File

@ -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);