Btrfs: sparse files!
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index c1a0add..5b87c4e 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -17,6 +17,7 @@
#include "transaction.h"
#include "btrfs_inode.h"
#include "ioctl.h"
+#include "print-tree.h"
struct btrfs_iget_args {
u64 ino;
@@ -421,14 +422,17 @@
struct btrfs_file_extent_item);
if (btrfs_file_extent_type(fi) !=
BTRFS_FILE_EXTENT_INLINE) {
+ u64 num_dec;
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) << 3;
- found_extent = 1;
+ num_dec = btrfs_file_extent_num_blocks(fi) << 3;
+ if (extent_start != 0) {
+ found_extent = 1;
+ inode->i_blocks -= num_dec;
+ }
}
}
ret = btrfs_del_item(trans, root, path);
@@ -448,6 +452,43 @@
return ret;
}
+static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ struct inode *inode = dentry->d_inode;
+ int err;
+
+ err = inode_change_ok(inode, attr);
+ if (err)
+ return err;
+
+ if (S_ISREG(inode->i_mode) &&
+ attr->ia_valid & ATTR_SIZE && attr->ia_size > inode->i_size) {
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ u64 mask = root->blocksize - 1;
+ u64 pos = (inode->i_size + mask) & ~mask;
+ u64 hole_size;
+
+ if (attr->ia_size < pos)
+ goto out;
+ hole_size = (attr->ia_size - pos + mask) & ~mask;
+ hole_size >>= inode->i_blkbits;
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, inode);
+ err = btrfs_insert_file_extent(trans, root, inode->i_ino,
+ pos, 0, 0, hole_size);
+ BUG_ON(err);
+ btrfs_end_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ }
+
+ err = inode_setattr(inode, attr);
+
+out:
+ return err;
+}
static void btrfs_delete_inode(struct inode *inode)
{
struct btrfs_trans_handle *trans;
@@ -1169,8 +1210,10 @@
if (found_type == BTRFS_FILE_EXTENT_REG) {
extent_start = extent_start >> inode->i_blkbits;
extent_end = extent_start + btrfs_file_extent_num_blocks(item);
+ err = 0;
+ if (blocknr == 0)
+ goto out;
if (iblock >= extent_start && iblock < extent_end) {
- err = 0;
btrfs_map_bh_to_logical(root, result, blocknr +
iblock - extent_start);
goto out;
@@ -1591,7 +1634,7 @@
ptr, bh->b_data, offset + write_bytes);
mark_buffer_dirty(path->nodes[0]);
btrfs_free_path(path);
- } else {
+ } else if (buffer_mapped(bh)) {
btrfs_csum_file_block(trans, root, inode->i_ino,
pages[i]->index << PAGE_CACHE_SHIFT,
kmap(pages[i]), PAGE_CACHE_SIZE);
@@ -1693,15 +1736,24 @@
goto out;
}
- search_start = extent_end;
+ if (found_inline) {
+ u64 mask = root->blocksize - 1;
+ search_start = (extent_end + mask) & ~mask;
+ } else
+ search_start = extent_end;
if (end < extent_end && end >= key.offset) {
if (found_extent) {
+ u64 disk_blocknr =
+ btrfs_file_extent_disk_blocknr(extent);
+ u64 disk_num_blocks =
+ btrfs_file_extent_disk_num_blocks(extent);
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);
+ if (disk_blocknr != 0) {
+ ret = btrfs_inc_extent_ref(trans, root,
+ disk_blocknr, disk_num_blocks);
+ BUG_ON(ret);
+ }
}
WARN_ON(found_inline);
bookend = 1;
@@ -1719,7 +1771,10 @@
old_num = btrfs_file_extent_num_blocks(extent);
*hint_block =
btrfs_file_extent_disk_blocknr(extent);
- inode->i_blocks -= (old_num - new_num) << 3;
+ if (btrfs_file_extent_disk_blocknr(extent)) {
+ inode->i_blocks -=
+ (old_num - new_num) << 3;
+ }
btrfs_set_file_extent_num_blocks(extent,
new_num);
mark_buffer_dirty(path->nodes[0]);
@@ -1745,7 +1800,7 @@
BUG_ON(ret);
btrfs_release_path(root, path);
extent = NULL;
- if (found_extent) {
+ if (found_extent && disk_blocknr != 0) {
inode->i_blocks -= extent_num_blocks << 3;
ret = btrfs_free_extent(trans, root,
disk_blocknr,
@@ -1785,18 +1840,19 @@
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);
+ (extent_end - end) >> inode->i_blkbits);
btrfs_set_file_extent_num_blocks(extent,
- btrfs_file_extent_num_blocks(&old) -
- ((end - key.offset) >> inode->i_blkbits));
+ (extent_end - end) >> inode->i_blkbits);
btrfs_set_file_extent_type(extent,
BTRFS_FILE_EXTENT_REG);
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;
+ if (btrfs_file_extent_disk_blocknr(&old) != 0) {
+ inode->i_blocks +=
+ btrfs_file_extent_num_blocks(extent) << 3;
+ }
ret = 0;
goto out;
}
@@ -1960,6 +2016,21 @@
~((u64)root->blocksize - 1), &hint_block);
BUG_ON(ret);
}
+ if (inode->i_size < start_pos) {
+ u64 last_pos_in_file;
+ u64 hole_size;
+ u64 mask = root->blocksize - 1;
+ last_pos_in_file = (inode->i_size + mask) & ~mask;
+ hole_size = (start_pos - last_pos_in_file + mask) & ~mask;
+ hole_size >>= inode->i_blkbits;
+ if (last_pos_in_file < start_pos) {
+ ret = btrfs_insert_file_extent(trans, root,
+ inode->i_ino,
+ last_pos_in_file,
+ 0, 0, hole_size);
+ }
+ BUG_ON(ret);
+ }
if (inode->i_size >= PAGE_CACHE_SIZE || pos + count < inode->i_size ||
pos + count - start_pos > BTRFS_MAX_INLINE_DATA_SIZE(root)) {
ret = btrfs_alloc_extent(trans, root, inode->i_ino,
@@ -1967,7 +2038,8 @@
&ins, 1);
BUG_ON(ret);
ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
- start_pos, ins.objectid, ins.offset);
+ start_pos, ins.objectid, ins.offset,
+ ins.offset);
BUG_ON(ret);
} else {
ins.offset = 0;
@@ -2044,10 +2116,13 @@
page->index << PAGE_CACHE_SHIFT,
kmap(page), PAGE_CACHE_SIZE);
if (ret) {
- printk("failed to verify ino %lu page %lu\n",
- page->mapping->host->i_ino,
- page->index);
- memset(page_address(page), 0, PAGE_CACHE_SIZE);
+ if (ret != -ENOENT) {
+ printk("failed to verify ino %lu page %lu\n",
+ page->mapping->host->i_ino,
+ page->index);
+ memset(page_address(page), 0, PAGE_CACHE_SIZE);
+ flush_dcache_page(page);
+ }
}
SetPageChecked(page);
kunmap(page);
@@ -2759,6 +2834,7 @@
.rmdir = btrfs_rmdir,
.rename = btrfs_rename,
.symlink = btrfs_symlink,
+ .setattr = btrfs_setattr,
};
static struct inode_operations btrfs_dir_ro_inode_operations = {
@@ -2788,6 +2864,7 @@
static struct inode_operations btrfs_file_inode_operations = {
.truncate = btrfs_truncate,
.getattr = btrfs_getattr,
+ .setattr = btrfs_setattr,
};
static struct file_operations btrfs_file_operations = {