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Btrfs: working file_write, reorganized key flags

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Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason 2007-04-18 16:15:28 -04:00 committed by David Woodhouse
parent 70b2befd0c
commit a429e51371
7 changed files with 178 additions and 186 deletions
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30
fs/btrfs/ctree.c
View File

@ -893,7 +893,11 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
}
left_nritems = btrfs_header_nritems(&left->header);
for (i = left_nritems - 1; i >= 0; i--) {
if (left_nritems == 0) {
btrfs_block_release(root, right_buf);
return 1;
}
for (i = left_nritems - 1; i >= 1; i--) {
item = left->items + i;
if (path->slots[0] == i)
push_space += data_size + sizeof(*item);
@ -907,6 +911,8 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
btrfs_block_release(root, right_buf);
return 1;
}
if (push_items == left_nritems)
WARN_ON(1);
right_nritems = btrfs_header_nritems(&right->header);
/* push left to right */
push_space = btrfs_item_end(left->items + left_nritems - push_items);
@ -943,6 +949,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
btrfs_mark_buffer_dirty(left_buf);
btrfs_mark_buffer_dirty(right_buf);
btrfs_memcpy(root, upper_node, &upper_node->ptrs[slot + 1].key,
&right->items[0].key, sizeof(struct btrfs_disk_key));
btrfs_mark_buffer_dirty(upper);
@ -1004,7 +1011,12 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
return 1;
}
for (i = 0; i < btrfs_header_nritems(&right->header); i++) {
if (btrfs_header_nritems(&right->header) == 0) {
btrfs_block_release(root, t);
return 1;
}
for (i = 0; i < btrfs_header_nritems(&right->header) - 1; i++) {
item = right->items + i;
if (path->slots[0] == i)
push_space += data_size + sizeof(*item);
@ -1018,6 +1030,8 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
btrfs_block_release(root, t);
return 1;
}
if (push_items == btrfs_header_nritems(&right->header))
WARN_ON(1);
/* push data from right to left */
btrfs_memcpy(root, left, left->items +
btrfs_header_nritems(&left->header),
@ -1064,7 +1078,6 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
btrfs_mark_buffer_dirty(t);
btrfs_mark_buffer_dirty(right_buf);
wret = fixup_low_keys(trans, root, path, &right->items[0].key, 1);
if (wret)
ret = wret;
@ -1181,6 +1194,12 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root
path->nodes[0] = right_buffer;
path->slots[0] = 0;
path->slots[1] -= 1;
if (path->slots[1] == 0) {
wret = fixup_low_keys(trans, root,
path, &disk_key, 1);
if (wret)
ret = wret;
}
return ret;
}
mid = slot;
@ -1241,6 +1260,11 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root
path->slots[1], 1);
if (wret)
ret = wret;
if (path->slots[1] == 0) {
wret = fixup_low_keys(trans, root, path, &disk_key, 1);
if (wret)
ret = wret;
}
btrfs_block_release(root, path->nodes[0]);
path->nodes[0] = right_buffer;
path->slots[0] = 0;

72
fs/btrfs/ctree.h
View File

@ -282,11 +282,12 @@ struct btrfs_root {
/* the lower bits in the key flags defines the item type */
#define BTRFS_KEY_TYPE_MAX 256
#define BTRFS_KEY_TYPE_MASK (BTRFS_KEY_TYPE_MAX - 1)
#define BTRFS_KEY_TYPE_SHIFT 24
#define BTRFS_KEY_TYPE_MASK (((u32)BTRFS_KEY_TYPE_MAX - 1) << \
BTRFS_KEY_TYPE_SHIFT)
#define BTRFS_KEY_OVERFLOW_MAX 128
#define BTRFS_KEY_OVERFLOW_SHIFT 8
#define BTRFS_KEY_OVERFLOW_MASK (0x7FULL << BTRFS_KEY_OVERFLOW_SHIFT)
#define BTRFS_KEY_OVERFLOW_MASK ((u32)BTRFS_KEY_OVERFLOW_MAX - 1)
/*
* inode items have the data typically returned from stat and store other
@ -586,56 +587,55 @@ static inline void btrfs_set_disk_key_flags(struct btrfs_disk_key *disk,
disk->flags = cpu_to_le32(val);
}
static inline u32 btrfs_disk_key_type(struct btrfs_disk_key *key)
{
return le32_to_cpu(key->flags) >> BTRFS_KEY_TYPE_SHIFT;
}
static inline void btrfs_set_disk_key_type(struct btrfs_disk_key *key,
u32 val)
{
u32 flags = btrfs_disk_key_flags(key);
BUG_ON(val >= BTRFS_KEY_TYPE_MAX);
val = val << BTRFS_KEY_TYPE_SHIFT;
flags = (flags & ~BTRFS_KEY_TYPE_MASK) | val;
btrfs_set_disk_key_flags(key, flags);
}
static inline u32 btrfs_key_type(struct btrfs_key *key)
{
return key->flags >> BTRFS_KEY_TYPE_SHIFT;
}
static inline void btrfs_set_key_type(struct btrfs_key *key, u32 val)
{
BUG_ON(val >= BTRFS_KEY_TYPE_MAX);
val = val << BTRFS_KEY_TYPE_SHIFT;
key->flags = (key->flags & ~(BTRFS_KEY_TYPE_MASK)) | val;
}
static inline u32 btrfs_key_overflow(struct btrfs_key *key)
{
u32 over = key->flags & BTRFS_KEY_OVERFLOW_MASK;
return over >> BTRFS_KEY_OVERFLOW_SHIFT;
return key->flags & BTRFS_KEY_OVERFLOW_MASK;
}
static inline void btrfs_set_key_overflow(struct btrfs_key *key, u32 over)
{
BUG_ON(over >= BTRFS_KEY_OVERFLOW_MAX);
over = over << BTRFS_KEY_OVERFLOW_SHIFT;
key->flags = (key->flags & ~((u64)BTRFS_KEY_OVERFLOW_MASK)) | over;
}
static inline u32 btrfs_key_type(struct btrfs_key *key)
{
return key->flags & BTRFS_KEY_TYPE_MASK;
}
static inline u32 btrfs_disk_key_type(struct btrfs_disk_key *key)
{
return le32_to_cpu(key->flags) & BTRFS_KEY_TYPE_MASK;
}
static inline void btrfs_set_key_type(struct btrfs_key *key, u32 type)
{
BUG_ON(type >= BTRFS_KEY_TYPE_MAX);
key->flags = (key->flags & ~((u64)BTRFS_KEY_TYPE_MASK)) | type;
}
static inline void btrfs_set_disk_key_type(struct btrfs_disk_key *key, u32 type)
{
u32 flags = btrfs_disk_key_flags(key);
BUG_ON(type >= BTRFS_KEY_TYPE_MAX);
flags = (flags & ~((u64)BTRFS_KEY_TYPE_MASK)) | type;
btrfs_set_disk_key_flags(key, flags);
key->flags = (key->flags & ~BTRFS_KEY_OVERFLOW_MASK) | over;
}
static inline u32 btrfs_disk_key_overflow(struct btrfs_disk_key *key)
{
u32 over = le32_to_cpu(key->flags) & BTRFS_KEY_OVERFLOW_MASK;
return over >> BTRFS_KEY_OVERFLOW_SHIFT;
return le32_to_cpu(key->flags) & BTRFS_KEY_OVERFLOW_MASK;
}
static inline void btrfs_set_disK_key_overflow(struct btrfs_disk_key *key,
static inline void btrfs_set_disk_key_overflow(struct btrfs_disk_key *key,
u32 over)
{
u32 flags = btrfs_disk_key_flags(key);
BUG_ON(over >= BTRFS_KEY_OVERFLOW_MAX);
over = over << BTRFS_KEY_OVERFLOW_SHIFT;
flags = (flags & ~((u64)BTRFS_KEY_OVERFLOW_MASK)) | over;
flags = (flags & ~BTRFS_KEY_OVERFLOW_MASK) | over;
btrfs_set_disk_key_flags(key, flags);
}

70
fs/btrfs/dir-item.c
View File

@ -58,30 +58,6 @@ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
btrfs_memcpy(root, path->nodes[0]->b_data, name_ptr, name, name_len);
btrfs_mark_buffer_dirty(path->nodes[0]);
/* FIXME, use some real flag for selecting the extra index */
if (root == root->fs_info->tree_root)
goto out;
btrfs_release_path(root, path);
btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
key.offset = location->objectid;
ret = insert_with_overflow(trans, root, path, &key, data_size);
// FIXME clear the dirindex bit
if (ret)
goto out;
dir_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
path->slots[0],
struct btrfs_dir_item);
btrfs_cpu_key_to_disk(&dir_item->location, location);
btrfs_set_dir_type(dir_item, type);
btrfs_set_dir_flags(dir_item, 0);
btrfs_set_dir_name_len(dir_item, name_len);
name_ptr = (char *)(dir_item + 1);
btrfs_memcpy(root, path->nodes[0]->b_data, name_ptr, name, name_len);
btrfs_mark_buffer_dirty(path->nodes[0]);
out:
btrfs_release_path(root, path);
btrfs_free_path(path);
@ -135,52 +111,6 @@ int btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root
return 1;
}
int btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 dir,
u64 objectid, int mod)
{
int ret;
struct btrfs_key key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
struct btrfs_disk_key *found_key;
struct btrfs_leaf *leaf;
int overflow = 0;
key.objectid = dir;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
key.offset = objectid;
while(1) {
btrfs_set_key_overflow(&key, overflow);
ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
if (ret < 0)
return ret;
if (ret > 0) {
if (overflow >= BTRFS_KEY_OVERFLOW_MAX)
return 1;
overflow++;
btrfs_set_key_overflow(&key, overflow);
btrfs_release_path(root, path);
continue;
} else {
/* found */
break;
}
}
leaf = btrfs_buffer_leaf(path->nodes[0]);
found_key = &leaf->items[path->slots[0]].key;
if (btrfs_disk_key_objectid(found_key) != dir ||
btrfs_disk_key_type(found_key) != BTRFS_DIR_INDEX_KEY)
return 1;
if (btrfs_disk_key_offset(found_key) == objectid)
return 0;
return 1;
}
int btrfs_match_dir_item_name(struct btrfs_root *root,
struct btrfs_path *path,
const char *name, int name_len)

4
fs/btrfs/extent-tree.c
View File

@ -35,8 +35,10 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
key.offset = num_blocks;
ret = btrfs_search_slot(trans, root->fs_info->extent_root, &key, path,
0, 1);
if (ret != 0)
if (ret != 0) {
printk("can't find block %Lu %Lu\n", blocknr, num_blocks);
BUG();
}
BUG_ON(ret != 0);
l = btrfs_buffer_leaf(path->nodes[0]);
item = btrfs_item_ptr(l, path->slots[0], struct btrfs_extent_item);

66
fs/btrfs/file-item.c
View File

@ -4,7 +4,7 @@
#include "transaction.h"
#define MAX_CSUM_ITEMS(r) ((((BTRFS_LEAF_DATA_SIZE(r) - \
sizeof(struct btrfs_item)) / \
sizeof(struct btrfs_item) * 2) / \
sizeof(struct btrfs_csum_item)) - 1))
int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
@ -19,11 +19,6 @@ int btrfs_insert_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 = pos;
file_key.flags = 0;
@ -40,6 +35,7 @@ int btrfs_insert_file_extent(struct btrfs_trans_handle *trans,
btrfs_set_file_extent_num_blocks(item, num_blocks);
btrfs_set_file_extent_generation(item, trans->transid);
btrfs_mark_buffer_dirty(path->nodes[0]);
btrfs_release_path(root, path);
btrfs_free_path(path);
return 0;
@ -57,6 +53,7 @@ struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans,
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;
@ -79,9 +76,11 @@ struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans,
}
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 /= sizeof(struct btrfs_csum_item);
if (csum_offset >= csums_in_item) {
ret = -EFBIG;
goto fail;
}
}
@ -128,16 +127,36 @@ 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);
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 / sizeof(struct btrfs_csum_item)) >=
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);
if (ret < 0)
@ -146,7 +165,6 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans,
BUG();
}
if (path->slots[0] == 0) {
btrfs_release_path(root, path);
goto insert;
}
path->slots[0]--;
@ -157,29 +175,36 @@ 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);
WARN_ON(1);
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));
u32 diff = (csum_offset + 1) * sizeof(struct btrfs_csum_item);
diff = diff - btrfs_item_size(leaf->items + path->slots[0]);
WARN_ON(diff != sizeof(struct btrfs_csum_item));
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)
if (ret != 0) {
printk("at insert for %Lu %u %Lu ret is %d\n", file_key.objectid, file_key.flags, file_key.offset, ret);
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;
found:
btrfs_check_bounds(item->csum, BTRFS_CSUM_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:
@ -210,6 +235,9 @@ int btrfs_csum_verify_file_block(struct btrfs_root *root,
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 = 1;
goto fail;
}

2
fs/btrfs/print-tree.c
View File

@ -19,7 +19,7 @@ void btrfs_print_leaf(struct btrfs_root *root, struct btrfs_leaf *l)
for (i = 0 ; i < nr ; i++) {
item = l->items + i;
type = btrfs_disk_key_type(&item->key);
printk("\titem %d key (%Lu %u %Lu) itemoff %d itemsize %d\n",
printk("\titem %d key (%Lu %x %Lu) itemoff %d itemsize %d\n",
i,
btrfs_disk_key_objectid(&item->key),
btrfs_disk_key_flags(&item->key),

120
fs/btrfs/super.c
View File

@ -150,11 +150,6 @@ static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
BUG_ON(ret);
btrfs_release_path(root, path);
ret = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
objectid, -1);
BUG_ON(ret);
ret = btrfs_del_item(trans, root, path);
BUG_ON(ret);
dentry->d_inode->i_ctime = dir->i_ctime;
err:
btrfs_release_path(root, path);
@ -329,8 +324,9 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
extent_start = btrfs_file_extent_disk_blocknr(fi);
extent_num_blocks =
btrfs_file_extent_disk_num_blocks(fi);
/* FIXME blocksize != 4096 */
inode->i_blocks -=
btrfs_file_extent_num_blocks(fi) >> 9;
btrfs_file_extent_num_blocks(fi) << 3;
found_extent = 1;
} else {
found_extent = 0;
@ -562,7 +558,7 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
if (btrfs_disk_key_objectid(&item->key) != key.objectid)
break;
if (btrfs_disk_key_type(&item->key) != key_type)
continue;
break;
if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
continue;
filp->f_pos = btrfs_disk_key_offset(&item->key);
@ -1285,29 +1281,27 @@ static int drop_extents(struct btrfs_trans_handle *trans,
struct btrfs_path *path;
u64 search_start = start;
int bookend;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
search_again:
ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
search_start, -1);
if (ret < 0)
goto out;
if (ret > 0) {
if (path->slots[0] == 0) {
ret = -ENOENT;
goto out;
}
path->slots[0]--;
}
while(1) {
btrfs_release_path(root, path);
ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
search_start, -1);
if (ret < 0)
goto out;
if (ret > 0) {
if (path->slots[0] == 0) {
ret = -ENOENT;
goto out;
}
path->slots[0]--;
}
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);
extent = btrfs_item_ptr(leaf, slot,
struct btrfs_file_extent_item);
extent_end = key.offset +
@ -1318,7 +1312,10 @@ search_again:
goto out;
}
if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY)
goto next_leaf;
goto out;
if (search_start >= extent_end)
goto out;
search_start = extent_end;
if (end < extent_end && end >= key.offset) {
memcpy(&old, extent, sizeof(old));
@ -1331,10 +1328,13 @@ search_again:
if (start > key.offset) {
u64 new_num;
u64 old_num;
/* truncate existing extent */
keep = 1;
WARN_ON(start & (root->blocksize - 1));
new_num = (start - key.offset) >> inode->i_blkbits;
old_num = btrfs_file_extent_num_blocks(extent);
inode->i_blocks -= (old_num - new_num) << 3;
btrfs_set_file_extent_num_blocks(extent, new_num);
mark_buffer_dirty(path->nodes[0]);
}
@ -1344,13 +1344,11 @@ search_again:
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);
inode->i_blocks -=
btrfs_file_extent_num_blocks(extent) << 3;
btrfs_release_path(root, path);
ret = btrfs_free_extent(trans, root, disk_blocknr,
disk_num_blocks, 0);
@ -1360,7 +1358,7 @@ search_again:
goto out;
}
if (!bookend)
goto search_again;
continue;
}
if (bookend) {
/* create bookend */
@ -1395,21 +1393,12 @@ search_again:
btrfs_set_file_extent_generation(extent,
btrfs_file_extent_generation(&old));
btrfs_mark_buffer_dirty(path->nodes[0]);
inode->i_blocks +=
btrfs_file_extent_num_blocks(extent) << 3;
ret = 0;
goto out;
}
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:
btrfs_free_path(path);
return ret;
@ -1445,15 +1434,6 @@ static int prepare_pages(struct btrfs_root *root,
}
offset = pos & (PAGE_CACHE_SIZE -1);
this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
#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]);
@ -1494,6 +1474,7 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
struct inode *inode = file->f_path.dentry->d_inode;
struct btrfs_root *root = BTRFS_I(inode)->root;
struct page *pages[8];
struct page *pinned[2] = { NULL, NULL };
unsigned long first_index;
unsigned long last_index;
u64 start_pos;
@ -1505,14 +1486,6 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
if (file->f_flags & O_DIRECT)
return -EINVAL;
pos = *ppos;
start_pos = pos & ~(root->blocksize - 1);
/* FIXME */
if (start_pos != pos)
return -EINVAL;
num_blocks = (count + pos - start_pos + root->blocksize - 1) >>
inode->i_blkbits;
vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
current->backing_dev_info = inode->i_mapping->backing_dev_info;
err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
@ -1524,10 +1497,37 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
if (err)
goto out;
file_update_time(file);
start_pos = pos & ~((u64)PAGE_CACHE_SIZE - 1);
num_blocks = (count + pos - start_pos + root->blocksize - 1) >>
inode->i_blkbits;
mutex_lock(&inode->i_mutex);
first_index = pos >> PAGE_CACHE_SHIFT;
last_index = (pos + count) >> PAGE_CACHE_SHIFT;
if ((first_index << PAGE_CACHE_SHIFT) < inode->i_size &&
(pos & (PAGE_CACHE_SIZE - 1))) {
pinned[0] = grab_cache_page(inode->i_mapping, first_index);
if (!PageUptodate(pinned[0])) {
ret = mpage_readpage(pinned[0], btrfs_get_block);
BUG_ON(ret);
} else {
unlock_page(pinned[0]);
}
}
if (first_index != last_index &&
(last_index << PAGE_CACHE_SHIFT) < inode->i_size &&
(count & (PAGE_CACHE_SIZE - 1))) {
pinned[1] = grab_cache_page(inode->i_mapping, last_index);
if (!PageUptodate(pinned[1])) {
ret = mpage_readpage(pinned[1], btrfs_get_block);
BUG_ON(ret);
} else {
unlock_page(pinned[1]);
}
}
mutex_lock(&root->fs_info->fs_mutex);
trans = btrfs_start_transaction(root, 1);
if (!trans) {
@ -1535,11 +1535,14 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
mutex_unlock(&root->fs_info->fs_mutex);
goto out_unlock;
}
/* FIXME blocksize != 4096 */
inode->i_blocks += num_blocks << 3;
if (start_pos < inode->i_size) {
/* FIXME blocksize != pagesize */
ret = drop_extents(trans, root, inode,
start_pos,
(pos + count + root->blocksize -1) &
~(root->blocksize - 1));
~((u64)root->blocksize - 1));
}
ret = btrfs_alloc_extent(trans, root, num_blocks, 1,
(u64)-1, &ins);
@ -1585,8 +1588,13 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
out_unlock:
mutex_unlock(&inode->i_mutex);
out:
if (pinned[0])
page_cache_release(pinned[0]);
if (pinned[1])
page_cache_release(pinned[1]);
*ppos = pos;
current->backing_dev_info = NULL;
mark_inode_dirty(inode);
return num_written ? num_written : err;
}