#include <linux/string.h>
#include <linux/smp_lock.h>
#include <linux/backing-dev.h>
+#include <linux/mpage.h>
+#include <linux/swap.h>
+#include <linux/writeback.h>
+#include <linux/statfs.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
+#include "btrfs_inode.h"
+#include "ioctl.h"
+#include "print-tree.h"
+
+struct btrfs_iget_args {
+ u64 ino;
+ struct btrfs_root *root;
+};
#define BTRFS_SUPER_MAGIC 0x9123682E
static struct inode_operations btrfs_dir_inode_operations;
+static struct inode_operations btrfs_symlink_inode_operations;
+static struct inode_operations btrfs_dir_ro_inode_operations;
static struct super_operations btrfs_super_ops;
static struct file_operations btrfs_dir_file_operations;
-
-#if 0
-/* some random number */
-
-static struct super_operations ramfs_ops;
-
-static struct backing_dev_info ramfs_backing_dev_info = {
- .ra_pages = 0, /* No readahead */
- .capabilities = BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_WRITEBACK |
- BDI_CAP_MAP_DIRECT | BDI_CAP_MAP_COPY |
- BDI_CAP_READ_MAP | BDI_CAP_WRITE_MAP | BDI_CAP_EXEC_MAP,
-};
-
-struct inode *ramfs_get_inode(struct super_block *sb, int mode, dev_t dev)
-{
- struct inode * inode = new_inode(sb);
-
- if (inode) {
- inode->i_mode = mode;
- inode->i_uid = current->fsuid;
- inode->i_gid = current->fsgid;
- inode->i_blocks = 0;
- inode->i_mapping->a_ops = &ramfs_aops;
- inode->i_mapping->backing_dev_info = &ramfs_backing_dev_info;
- inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
- switch (mode & S_IFMT) {
- default:
- init_special_inode(inode, mode, dev);
- break;
- case S_IFREG:
- inode->i_op = &ramfs_file_inode_operations;
- inode->i_fop = &ramfs_file_operations;
- break;
- case S_IFDIR:
- inode->i_op = &ramfs_dir_inode_operations;
- inode->i_fop = &simple_dir_operations;
-
- /* directory inodes start off with i_nlink == 2 (for "." entry) */
- inc_nlink(inode);
- break;
- case S_IFLNK:
- inode->i_op = &page_symlink_inode_operations;
- break;
- }
- }
- return inode;
-}
-
-/*
- * File creation. Allocate an inode, and we're done..
- */
-/* SMP-safe */
-static int
-ramfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
-{
- struct inode * inode = ramfs_get_inode(dir->i_sb, mode, dev);
- int error = -ENOSPC;
-
- if (inode) {
- if (dir->i_mode & S_ISGID) {
- inode->i_gid = dir->i_gid;
- if (S_ISDIR(mode))
- inode->i_mode |= S_ISGID;
- }
- d_instantiate(dentry, inode);
- dget(dentry); /* Extra count - pin the dentry in core */
- error = 0;
- dir->i_mtime = dir->i_ctime = CURRENT_TIME;
- }
- return error;
-}
-
-static int ramfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
-{
- int retval = ramfs_mknod(dir, dentry, mode | S_IFDIR, 0);
- if (!retval)
- inc_nlink(dir);
- return retval;
-}
-
-static int ramfs_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd)
-{
- return ramfs_mknod(dir, dentry, mode | S_IFREG, 0);
-}
-
-static int ramfs_symlink(struct inode * dir, struct dentry *dentry, const char * symname)
-{
- struct inode *inode;
- int error = -ENOSPC;
-
- inode = ramfs_get_inode(dir->i_sb, S_IFLNK|S_IRWXUGO, 0);
- if (inode) {
- int l = strlen(symname)+1;
- error = page_symlink(inode, symname, l);
- if (!error) {
- if (dir->i_mode & S_ISGID)
- inode->i_gid = dir->i_gid;
- d_instantiate(dentry, inode);
- dget(dentry);
- dir->i_mtime = dir->i_ctime = CURRENT_TIME;
- } else
- iput(inode);
- }
- return error;
-}
-
-static struct inode_operations ramfs_dir_inode_operations = {
- .create = ramfs_create,
- .lookup = simple_lookup,
- .link = simple_link,
- .unlink = simple_unlink,
- .symlink = ramfs_symlink,
- .mkdir = ramfs_mkdir,
- .rmdir = simple_rmdir,
- .mknod = ramfs_mknod,
- .rename = simple_rename,
+static struct inode_operations btrfs_file_inode_operations;
+static struct address_space_operations btrfs_aops;
+static struct address_space_operations btrfs_symlink_aops;
+static struct file_operations btrfs_file_operations;
+
+static int drop_extents(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode,
+ u64 start, u64 end, u64 *hint_block);
+static int btrfs_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *result, int create);
+
+
+#define S_SHIFT 12
+static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
+ [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
+ [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
+ [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
+ [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
+ [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
+ [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
+ [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
};
-#endif
static void btrfs_read_locked_inode(struct inode *inode)
{
- struct btrfs_path path;
+ struct btrfs_path *path;
struct btrfs_inode_item *inode_item;
- struct btrfs_root *root = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_key location;
+ struct btrfs_block_group_cache *alloc_group;
+ u64 alloc_group_block;
int ret;
- btrfs_init_path(&path);
- ret = btrfs_lookup_inode(NULL, root, &path, inode->i_ino, 0);
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ btrfs_init_path(path);
+ mutex_lock(&root->fs_info->fs_mutex);
+
+ memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
+ ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
if (ret) {
- make_bad_inode(inode);
- btrfs_release_path(root, &path);
- return;
+ btrfs_free_path(path);
+ goto make_bad;
}
- inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]),
- path.slots[0],
+ inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+ path->slots[0],
struct btrfs_inode_item);
inode->i_mode = btrfs_inode_mode(inode_item);
inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
inode->i_blocks = btrfs_inode_nblocks(inode_item);
inode->i_generation = btrfs_inode_generation(inode_item);
- btrfs_release_path(root, &path);
+ alloc_group_block = btrfs_inode_block_group(inode_item);
+ ret = radix_tree_gang_lookup(&root->fs_info->block_group_radix,
+ (void **)&alloc_group,
+ alloc_group_block, 1);
+ BUG_ON(!ret);
+ BTRFS_I(inode)->block_group = alloc_group;
+
+ btrfs_free_path(path);
+ inode_item = NULL;
+
+ mutex_unlock(&root->fs_info->fs_mutex);
+
switch (inode->i_mode & S_IFMT) {
#if 0
default:
break;
#endif
case S_IFREG:
+ inode->i_mapping->a_ops = &btrfs_aops;
+ inode->i_fop = &btrfs_file_operations;
+ inode->i_op = &btrfs_file_inode_operations;
break;
case S_IFDIR:
- inode->i_op = &btrfs_dir_inode_operations;
inode->i_fop = &btrfs_dir_file_operations;
+ if (root == root->fs_info->tree_root)
+ inode->i_op = &btrfs_dir_ro_inode_operations;
+ else
+ inode->i_op = &btrfs_dir_inode_operations;
break;
case S_IFLNK:
- // inode->i_op = &page_symlink_inode_operations;
+ inode->i_op = &btrfs_symlink_inode_operations;
+ inode->i_mapping->a_ops = &btrfs_symlink_aops;
break;
}
return;
+
+make_bad:
+ btrfs_release_path(root, path);
+ btrfs_free_path(path);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ make_bad_inode(inode);
}
-static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
+static void fill_inode_item(struct btrfs_inode_item *item,
+ struct inode *inode)
{
- struct btrfs_path path;
- struct btrfs_root *root;
- struct btrfs_trans_handle *trans;
+ btrfs_set_inode_uid(item, inode->i_uid);
+ btrfs_set_inode_gid(item, inode->i_gid);
+ btrfs_set_inode_size(item, inode->i_size);
+ btrfs_set_inode_mode(item, inode->i_mode);
+ btrfs_set_inode_nlink(item, inode->i_nlink);
+ btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
+ btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
+ btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
+ btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
+ btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
+ btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
+ btrfs_set_inode_nblocks(item, inode->i_blocks);
+ btrfs_set_inode_generation(item, inode->i_generation);
+ btrfs_set_inode_block_group(item,
+ BTRFS_I(inode)->block_group->key.objectid);
+}
+
+static int btrfs_update_inode(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode)
+{
+ struct btrfs_inode_item *inode_item;
+ struct btrfs_path *path;
+ int ret;
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ btrfs_init_path(path);
+ ret = btrfs_lookup_inode(trans, root, path,
+ &BTRFS_I(inode)->location, 1);
+ if (ret) {
+ if (ret > 0)
+ ret = -ENOENT;
+ goto failed;
+ }
+
+ inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+ path->slots[0],
+ struct btrfs_inode_item);
+
+ fill_inode_item(inode_item, inode);
+ btrfs_mark_buffer_dirty(path->nodes[0]);
+ ret = 0;
+failed:
+ btrfs_release_path(root, path);
+ btrfs_free_path(path);
+ return ret;
+}
+
+
+static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *dir,
+ struct dentry *dentry)
+{
+ struct btrfs_path *path;
const char *name = dentry->d_name.name;
int name_len = dentry->d_name.len;
- int ret;
+ int ret = 0;
u64 objectid;
struct btrfs_dir_item *di;
- btrfs_init_path(&path);
- root = btrfs_sb(dir->i_sb);
- mutex_lock(&root->fs_info->fs_mutex);
- trans = btrfs_start_transaction(root, 1);
-
- ret = btrfs_lookup_dir_item(trans, root, &path, dir->i_ino,
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ btrfs_init_path(path);
+ di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
name, name_len, -1);
- if (ret < 0)
+ if (IS_ERR(di)) {
+ ret = PTR_ERR(di);
goto err;
- if (ret > 0) {
+ }
+ if (!di) {
ret = -ENOENT;
goto err;
}
- di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
- struct btrfs_dir_item);
- objectid = btrfs_dir_objectid(di);
+ objectid = btrfs_disk_key_objectid(&di->location);
+ ret = btrfs_delete_one_dir_name(trans, root, path, di);
+ BUG_ON(ret);
+ btrfs_release_path(root, path);
- ret = btrfs_del_item(trans, root, &path);
+ di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
+ objectid, name, name_len, -1);
+ if (IS_ERR(di)) {
+ ret = PTR_ERR(di);
+ goto err;
+ }
+ if (!di) {
+ ret = -ENOENT;
+ goto err;
+ }
+ ret = btrfs_delete_one_dir_name(trans, root, path, di);
BUG_ON(ret);
+
dentry->d_inode->i_ctime = dir->i_ctime;
err:
- btrfs_release_path(root, &path);
+ btrfs_free_path(path);
+ if (!ret) {
+ dir->i_size -= name_len * 2;
+ btrfs_update_inode(trans, root, dir);
+ drop_nlink(dentry->d_inode);
+ btrfs_update_inode(trans, root, dentry->d_inode);
+ dir->i_sb->s_dirt = 1;
+ }
+ return ret;
+}
+
+static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
+{
+ struct btrfs_root *root;
+ struct btrfs_trans_handle *trans;
+ int ret;
+
+ root = BTRFS_I(dir)->root;
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, dir);
+ ret = btrfs_unlink_trans(trans, root, dir, dentry);
btrfs_end_transaction(trans, root);
mutex_unlock(&root->fs_info->fs_mutex);
- if (ret == 0)
- inode_dec_link_count(dentry->d_inode);
+ btrfs_btree_balance_dirty(root);
return ret;
}
+static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
+{
+ struct inode *inode = dentry->d_inode;
+ int err;
+ int ret;
+ struct btrfs_root *root = BTRFS_I(dir)->root;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_key found_key;
+ int found_type;
+ struct btrfs_leaf *leaf;
+ char *goodnames = "..";
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ btrfs_init_path(path);
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, dir);
+ key.objectid = inode->i_ino;
+ key.offset = (u64)-1;
+ key.flags = (u32)-1;
+ while(1) {
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret < 0) {
+ err = ret;
+ goto out;
+ }
+ BUG_ON(ret == 0);
+ if (path->slots[0] == 0) {
+ err = -ENOENT;
+ goto out;
+ }
+ path->slots[0]--;
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ btrfs_disk_key_to_cpu(&found_key,
+ &leaf->items[path->slots[0]].key);
+ found_type = btrfs_key_type(&found_key);
+ if (found_key.objectid != inode->i_ino) {
+ err = -ENOENT;
+ goto out;
+ }
+ if ((found_type != BTRFS_DIR_ITEM_KEY &&
+ found_type != BTRFS_DIR_INDEX_KEY) ||
+ (!btrfs_match_dir_item_name(root, path, goodnames, 2) &&
+ !btrfs_match_dir_item_name(root, path, goodnames, 1))) {
+ err = -ENOTEMPTY;
+ goto out;
+ }
+ ret = btrfs_del_item(trans, root, path);
+ BUG_ON(ret);
+
+ if (found_type == BTRFS_DIR_ITEM_KEY && found_key.offset == 1)
+ break;
+ btrfs_release_path(root, path);
+ }
+ ret = 0;
+ btrfs_release_path(root, path);
+
+ /* now the directory is empty */
+ err = btrfs_unlink_trans(trans, root, dir, dentry);
+ if (!err) {
+ inode->i_size = 0;
+ }
+out:
+ btrfs_release_path(root, path);
+ btrfs_free_path(path);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ ret = btrfs_end_transaction(trans, root);
+ btrfs_btree_balance_dirty(root);
+ if (ret && !err)
+ err = ret;
+ return err;
+}
+
static int btrfs_free_inode(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct inode *inode)
{
- u64 objectid = inode->i_ino;
- struct btrfs_path path;
- struct btrfs_inode_map_item *map;
- struct btrfs_key stat_data_key;
+ struct btrfs_path *path;
int ret;
+
clear_inode(inode);
- btrfs_init_path(&path);
- ret = btrfs_lookup_inode_map(trans, root, &path, objectid, -1);
- if (ret) {
- if (ret > 0)
- ret = -ENOENT;
- btrfs_release_path(root, &path);
- goto error;
- }
- map = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
- struct btrfs_inode_map_item);
- btrfs_disk_key_to_cpu(&stat_data_key, &map->key);
- ret = btrfs_del_item(trans, root->fs_info->inode_root, &path);
- BUG_ON(ret);
- btrfs_release_path(root, &path);
- btrfs_init_path(&path);
- ret = btrfs_lookup_inode(trans, root, &path, objectid, -1);
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ btrfs_init_path(path);
+ ret = btrfs_lookup_inode(trans, root, path,
+ &BTRFS_I(inode)->location, -1);
BUG_ON(ret);
- ret = btrfs_del_item(trans, root, &path);
+ ret = btrfs_del_item(trans, root, path);
BUG_ON(ret);
- btrfs_release_path(root, &path);
+ btrfs_free_path(path);
+ return ret;
+}
+
+static void reada_truncate(struct btrfs_root *root, struct btrfs_path *path,
+ u64 objectid)
+{
+ struct btrfs_node *node;
+ int i;
+ int nritems;
+ u64 item_objectid;
+ u64 blocknr;
+ int slot;
+ int ret;
+
+ if (!path->nodes[1])
+ return;
+ node = btrfs_buffer_node(path->nodes[1]);
+ slot = path->slots[1];
+ if (slot == 0)
+ return;
+ nritems = btrfs_header_nritems(&node->header);
+ for (i = slot - 1; i >= 0; i--) {
+ item_objectid = btrfs_disk_key_objectid(&node->ptrs[i].key);
+ if (item_objectid != objectid)
+ break;
+ blocknr = btrfs_node_blockptr(node, i);
+ ret = readahead_tree_block(root, blocknr);
+ if (ret)
+ break;
+ }
+}
+
+static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode)
+{
+ int ret;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct btrfs_disk_key *found_key;
+ u32 found_type;
+ struct btrfs_leaf *leaf;
+ struct btrfs_file_extent_item *fi;
+ u64 extent_start = 0;
+ u64 extent_num_blocks = 0;
+ u64 item_end = 0;
+ int found_extent;
+ int del_item;
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ /* FIXME, add redo link to tree so we don't leak on crash */
+ key.objectid = inode->i_ino;
+ key.offset = (u64)-1;
+ key.flags = (u32)-1;
+ while(1) {
+ btrfs_init_path(path);
+ fi = NULL;
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret < 0) {
+ goto error;
+ }
+ if (ret > 0) {
+ BUG_ON(path->slots[0] == 0);
+ path->slots[0]--;
+ }
+ reada_truncate(root, path, inode->i_ino);
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ found_key = &leaf->items[path->slots[0]].key;
+ found_type = btrfs_disk_key_type(found_key);
+ if (btrfs_disk_key_objectid(found_key) != inode->i_ino)
+ break;
+ if (found_type != BTRFS_CSUM_ITEM_KEY &&
+ found_type != BTRFS_DIR_ITEM_KEY &&
+ found_type != BTRFS_DIR_INDEX_KEY &&
+ found_type != BTRFS_EXTENT_DATA_KEY)
+ break;
+ item_end = btrfs_disk_key_offset(found_key);
+ if (found_type == BTRFS_EXTENT_DATA_KEY) {
+ fi = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+ path->slots[0],
+ struct btrfs_file_extent_item);
+ if (btrfs_file_extent_type(fi) !=
+ BTRFS_FILE_EXTENT_INLINE) {
+ item_end += btrfs_file_extent_num_blocks(fi) <<
+ inode->i_blkbits;
+ }
+ }
+ if (found_type == BTRFS_CSUM_ITEM_KEY) {
+ ret = btrfs_csum_truncate(trans, root, path,
+ inode->i_size);
+ BUG_ON(ret);
+ }
+ if (item_end < inode->i_size) {
+ if (found_type) {
+ btrfs_set_key_type(&key, found_type - 1);
+ continue;
+ }
+ break;
+ }
+ if (btrfs_disk_key_offset(found_key) >= inode->i_size)
+ del_item = 1;
+ else
+ del_item = 0;
+ found_extent = 0;
+
+ if (found_type == BTRFS_EXTENT_DATA_KEY &&
+ btrfs_file_extent_type(fi) !=
+ BTRFS_FILE_EXTENT_INLINE) {
+ u64 num_dec;
+ if (!del_item) {
+ u64 orig_num_blocks =
+ btrfs_file_extent_num_blocks(fi);
+ extent_num_blocks = inode->i_size -
+ btrfs_disk_key_offset(found_key) +
+ root->blocksize - 1;
+ extent_num_blocks >>= inode->i_blkbits;
+ btrfs_set_file_extent_num_blocks(fi,
+ extent_num_blocks);
+ inode->i_blocks -= (orig_num_blocks -
+ extent_num_blocks) << 3;
+ mark_buffer_dirty(path->nodes[0]);
+ } else {
+ extent_start =
+ btrfs_file_extent_disk_blocknr(fi);
+ extent_num_blocks =
+ btrfs_file_extent_disk_num_blocks(fi);
+ /* FIXME blocksize != 4096 */
+ num_dec = btrfs_file_extent_num_blocks(fi) << 3;
+ if (extent_start != 0) {
+ found_extent = 1;
+ inode->i_blocks -= num_dec;
+ }
+ }
+ }
+ if (del_item) {
+ ret = btrfs_del_item(trans, root, path);
+ BUG_ON(ret);
+ } else {
+ break;
+ }
+ btrfs_release_path(root, path);
+ if (found_extent) {
+ ret = btrfs_free_extent(trans, root, extent_start,
+ extent_num_blocks, 0);
+ BUG_ON(ret);
+ }
+ }
+ ret = 0;
error:
+ btrfs_release_path(root, path);
+ btrfs_free_path(path);
+ inode->i_sb->s_dirt = 1;
+ return ret;
+}
+
+static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
+{
+ struct inode *inode = mapping->host;
+ unsigned blocksize = 1 << inode->i_blkbits;
+ pgoff_t index = from >> PAGE_CACHE_SHIFT;
+ unsigned offset = from & (PAGE_CACHE_SIZE-1);
+ struct page *page;
+ char *kaddr;
+ int ret = 0;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ u64 alloc_hint;
+ struct btrfs_key ins;
+ struct btrfs_trans_handle *trans;
+
+ if ((offset & (blocksize - 1)) == 0)
+ goto out;
+
+ ret = -ENOMEM;
+ page = grab_cache_page(mapping, index);
+ if (!page)
+ goto out;
+
+ if (!PageUptodate(page)) {
+ ret = mpage_readpage(page, btrfs_get_block);
+ lock_page(page);
+ if (!PageUptodate(page)) {
+ ret = -EIO;
+ goto out;
+ }
+ }
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, inode);
+
+ ret = drop_extents(trans, root, inode, page->index << PAGE_CACHE_SHIFT,
+ (page->index + 1) << PAGE_CACHE_SHIFT, &alloc_hint);
+ BUG_ON(ret);
+ ret = btrfs_alloc_extent(trans, root, inode->i_ino, 1,
+ alloc_hint, (u64)-1, &ins, 1);
+ BUG_ON(ret);
+ ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
+ page->index << PAGE_CACHE_SHIFT,
+ ins.objectid, 1, 1);
+ BUG_ON(ret);
+ SetPageChecked(page);
+ kaddr = kmap(page);
+ memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
+ flush_dcache_page(page);
+ btrfs_csum_file_block(trans, root, inode->i_ino,
+ page->index << PAGE_CACHE_SHIFT,
+ kaddr, PAGE_CACHE_SIZE);
+ kunmap(page);
+ btrfs_end_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+
+ set_page_dirty(page);
+ unlock_page(page);
+ page_cache_release(page);
+out:
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;
+
+ btrfs_truncate_page(inode->i_mapping, inode->i_size);
+
+ 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);
+ }
+out:
+ err = inode_setattr(inode, attr);
+
+ return err;
+}
static void btrfs_delete_inode(struct inode *inode)
{
struct btrfs_trans_handle *trans;
- struct btrfs_root *root = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ int ret;
+
truncate_inode_pages(&inode->i_data, 0);
if (is_bad_inode(inode)) {
goto no_delete;
}
inode->i_size = 0;
- if (inode->i_blocks)
- WARN_ON(1);
-
mutex_lock(&root->fs_info->fs_mutex);
trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, inode);
+ ret = btrfs_truncate_in_trans(trans, root, inode);
+ BUG_ON(ret);
btrfs_free_inode(trans, root, inode);
btrfs_end_transaction(trans, root);
mutex_unlock(&root->fs_info->fs_mutex);
+ btrfs_btree_balance_dirty(root);
return;
no_delete:
clear_inode(inode);
}
-
static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
- ino_t *ino)
+ struct btrfs_key *location)
{
const char *name = dentry->d_name.name;
int namelen = dentry->d_name.len;
struct btrfs_dir_item *di;
- struct btrfs_path path;
- struct btrfs_root *root = btrfs_sb(dir->i_sb);
+ struct btrfs_path *path;
+ struct btrfs_root *root = BTRFS_I(dir)->root;
int ret;
- btrfs_init_path(&path);
- ret = btrfs_lookup_dir_item(NULL, root, &path, dir->i_ino, name,
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ btrfs_init_path(path);
+ di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
namelen, 0);
- if (ret || !btrfs_match_dir_item_name(root, &path, name, namelen)) {
- *ino = 0;
+ if (!di || IS_ERR(di)) {
+ location->objectid = 0;
+ ret = 0;
goto out;
}
- di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
- struct btrfs_dir_item);
- *ino = btrfs_dir_objectid(di);
+ btrfs_disk_key_to_cpu(location, &di->location);
out:
- btrfs_release_path(root, &path);
+ btrfs_release_path(root, path);
+ btrfs_free_path(path);
return ret;
}
+static int fixup_tree_root_location(struct btrfs_root *root,
+ struct btrfs_key *location,
+ struct btrfs_root **sub_root)
+{
+ struct btrfs_path *path;
+ struct btrfs_root_item *ri;
+
+ if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
+ return 0;
+ if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
+ return 0;
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ mutex_lock(&root->fs_info->fs_mutex);
+
+ *sub_root = btrfs_read_fs_root(root->fs_info, location);
+ if (IS_ERR(*sub_root))
+ return PTR_ERR(*sub_root);
+
+ ri = &(*sub_root)->root_item;
+ location->objectid = btrfs_root_dirid(ri);
+ location->flags = 0;
+ btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
+ location->offset = 0;
+
+ btrfs_free_path(path);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ return 0;
+}
+
+static int btrfs_init_locked_inode(struct inode *inode, void *p)
+{
+ struct btrfs_iget_args *args = p;
+ inode->i_ino = args->ino;
+ BTRFS_I(inode)->root = args->root;
+ return 0;
+}
+
+static int btrfs_find_actor(struct inode *inode, void *opaque)
+{
+ struct btrfs_iget_args *args = opaque;
+ return (args->ino == inode->i_ino &&
+ args->root == BTRFS_I(inode)->root);
+}
+
+static struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
+ struct btrfs_root *root)
+{
+ struct inode *inode;
+ struct btrfs_iget_args args;
+ args.ino = objectid;
+ args.root = root;
+
+ inode = iget5_locked(s, objectid, btrfs_find_actor,
+ btrfs_init_locked_inode,
+ (void *)&args);
+ return inode;
+}
+
static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd)
{
struct inode * inode;
- ino_t ino;
+ struct btrfs_inode *bi = BTRFS_I(dir);
+ struct btrfs_root *root = bi->root;
+ struct btrfs_root *sub_root = root;
+ struct btrfs_key location;
int ret;
if (dentry->d_name.len > BTRFS_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
-
- ret = btrfs_inode_by_name(dir, dentry, &ino);
+ mutex_lock(&root->fs_info->fs_mutex);
+ ret = btrfs_inode_by_name(dir, dentry, &location);
+ mutex_unlock(&root->fs_info->fs_mutex);
if (ret < 0)
return ERR_PTR(ret);
inode = NULL;
- if (ino) {
- inode = iget(dir->i_sb, ino);
+ if (location.objectid) {
+ ret = fixup_tree_root_location(root, &location, &sub_root);
+ if (ret < 0)
+ return ERR_PTR(ret);
+ if (ret > 0)
+ return ERR_PTR(-ENOENT);
+ inode = btrfs_iget_locked(dir->i_sb, location.objectid,
+ sub_root);
if (!inode)
return ERR_PTR(-EACCES);
+ if (inode->i_state & I_NEW) {
+ if (sub_root != root) {
+printk("adding new root for inode %lu root %p (found %p)\n", inode->i_ino, sub_root, BTRFS_I(inode)->root);
+ igrab(inode);
+ sub_root->inode = inode;
+ }
+ BTRFS_I(inode)->root = sub_root;
+ memcpy(&BTRFS_I(inode)->location, &location,
+ sizeof(location));
+ btrfs_read_locked_inode(inode);
+ unlock_new_inode(inode);
+ }
}
return d_splice_alias(inode, dentry);
}
+static void reada_leaves(struct btrfs_root *root, struct btrfs_path *path,
+ u64 objectid)
+{
+ struct btrfs_node *node;
+ int i;
+ u32 nritems;
+ u64 item_objectid;
+ u64 blocknr;
+ int slot;
+ int ret;
+
+ if (!path->nodes[1])
+ return;
+ node = btrfs_buffer_node(path->nodes[1]);
+ slot = path->slots[1];
+ nritems = btrfs_header_nritems(&node->header);
+ for (i = slot + 1; i < nritems; i++) {
+ item_objectid = btrfs_disk_key_objectid(&node->ptrs[i].key);
+ if (item_objectid != objectid)
+ break;
+ blocknr = btrfs_node_blockptr(node, i);
+ ret = readahead_tree_block(root, blocknr);
+ if (ret)
+ break;
+ }
+}
+static unsigned char btrfs_filetype_table[] = {
+ DT_UNKNOWN, DT_REG, DT_DIR, DT_CHR, DT_BLK, DT_FIFO, DT_SOCK, DT_LNK
+};
+
static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
struct inode *inode = filp->f_path.dentry->d_inode;
- struct btrfs_root *root = btrfs_sb(inode->i_sb);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_item *item;
struct btrfs_dir_item *di;
struct btrfs_key key;
- struct btrfs_path path;
+ struct btrfs_path *path;
int ret;
u32 nritems;
struct btrfs_leaf *leaf;
int slot;
int advance;
- unsigned char d_type = DT_UNKNOWN;
+ unsigned char d_type;
int over = 0;
-
+ u32 di_cur;
+ u32 di_total;
+ u32 di_len;
+ int key_type = BTRFS_DIR_INDEX_KEY;
+
+ /* FIXME, use a real flag for deciding about the key type */
+ if (root->fs_info->tree_root == root)
+ key_type = BTRFS_DIR_ITEM_KEY;
+ mutex_lock(&root->fs_info->fs_mutex);
key.objectid = inode->i_ino;
key.flags = 0;
- btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
+ btrfs_set_key_type(&key, key_type);
key.offset = filp->f_pos;
- btrfs_init_path(&path);
- ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
- if (ret < 0) {
+ path = btrfs_alloc_path();
+ btrfs_init_path(path);
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (ret < 0)
goto err;
- }
advance = 0;
+ reada_leaves(root, path, inode->i_ino);
while(1) {
- leaf = btrfs_buffer_leaf(path.nodes[0]);
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
nritems = btrfs_header_nritems(&leaf->header);
- slot = path.slots[0];
- if (advance) {
- if (slot == nritems -1) {
- ret = btrfs_next_leaf(root, &path);
+ slot = path->slots[0];
+ if (advance || slot >= nritems) {
+ if (slot >= nritems -1) {
+ reada_leaves(root, path, inode->i_ino);
+ ret = btrfs_next_leaf(root, path);
if (ret)
break;
- leaf = btrfs_buffer_leaf(path.nodes[0]);
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
nritems = btrfs_header_nritems(&leaf->header);
- slot = path.slots[0];
-#if 0
- page_cache_readahead(
- inode->i_sb->s_bdev->bd_inode->i_mapping,
- &filp->f_ra, filp,
- path.nodes[0]->b_blocknr >>
- (PAGE_CACHE_SHIFT - inode->i_blkbits), 1);
-#endif
+ slot = path->slots[0];
} else {
slot++;
- path.slots[0]++;
+ path->slots[0]++;
}
}
advance = 1;
item = leaf->items + slot;
if (btrfs_disk_key_objectid(&item->key) != key.objectid)
break;
- if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_ITEM_KEY)
- continue;
+ if (btrfs_disk_key_type(&item->key) != key_type)
+ break;
if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
continue;
+ filp->f_pos = btrfs_disk_key_offset(&item->key);
+ advance = 1;
di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
- over = filldir(dirent, (const char *)(di + 1),
- btrfs_dir_name_len(di),
- btrfs_disk_key_offset(&item->key),
- btrfs_dir_objectid(di), d_type);
- if (over) {
- filp->f_pos = btrfs_disk_key_offset(&item->key);
- break;
+ di_cur = 0;
+ di_total = btrfs_item_size(leaf->items + slot);
+ while(di_cur < di_total) {
+ d_type = btrfs_filetype_table[btrfs_dir_type(di)];
+ over = filldir(dirent, (const char *)(di + 1),
+ btrfs_dir_name_len(di),
+ btrfs_disk_key_offset(&item->key),
+ btrfs_disk_key_objectid(&di->location),
+ d_type);
+ if (over)
+ goto nopos;
+ di_len = btrfs_dir_name_len(di) + sizeof(*di);
+ di_cur += di_len;
+ di = (struct btrfs_dir_item *)((char *)di + di_len);
}
- filp->f_pos = btrfs_disk_key_offset(&item->key) + 1;
}
+ filp->f_pos++;
+nopos:
ret = 0;
err:
- btrfs_release_path(root, &path);
+ btrfs_release_path(root, path);
+ btrfs_free_path(path);
+ mutex_unlock(&root->fs_info->fs_mutex);
return ret;
}
struct inode * inode;
struct dentry * root_dentry;
struct btrfs_super_block *disk_super;
- struct buffer_head *bh;
- struct btrfs_root *root;
+ struct btrfs_root *tree_root;
+ struct btrfs_inode *bi;
sb->s_maxbytes = MAX_LFS_FILESIZE;
- sb->s_blocksize = PAGE_CACHE_SIZE;
- sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
sb->s_magic = BTRFS_SUPER_MAGIC;
sb->s_op = &btrfs_super_ops;
sb->s_time_gran = 1;
- bh = sb_bread(sb, BTRFS_SUPER_INFO_OFFSET / sb->s_blocksize);
- if (!bh) {
- printk("btrfs: unable to read on disk super\n");
- return -EIO;
- }
- disk_super = (struct btrfs_super_block *)bh->b_data;
- root = open_ctree(sb, bh, disk_super);
- sb->s_fs_info = root;
- if (!root) {
+ tree_root = open_ctree(sb);
+
+ if (!tree_root) {
printk("btrfs: open_ctree failed\n");
return -EIO;
}
+ sb->s_fs_info = tree_root;
+ disk_super = tree_root->fs_info->disk_super;
printk("read in super total blocks %Lu root %Lu\n",
btrfs_super_total_blocks(disk_super),
btrfs_super_root_dir(disk_super));
- inode = iget_locked(sb, btrfs_super_root_dir(disk_super));
+ inode = btrfs_iget_locked(sb, btrfs_super_root_dir(disk_super),
+ tree_root);
+ bi = BTRFS_I(inode);
+ bi->location.objectid = inode->i_ino;
+ bi->location.offset = 0;
+ bi->location.flags = 0;
+ bi->root = tree_root;
+ btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY);
+
if (!inode)
return -ENOMEM;
if (inode->i_state & I_NEW) {
return 0;
}
-static void fill_inode_item(struct btrfs_inode_item *item,
- struct inode *inode)
+static int btrfs_write_inode(struct inode *inode, int wait)
{
- btrfs_set_inode_uid(item, inode->i_uid);
- btrfs_set_inode_gid(item, inode->i_gid);
- btrfs_set_inode_size(item, inode->i_size);
- btrfs_set_inode_mode(item, inode->i_mode);
- btrfs_set_inode_nlink(item, inode->i_nlink);
- btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
- btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
- btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
- btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
- btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
- btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
- btrfs_set_inode_nblocks(item, inode->i_blocks);
- btrfs_set_inode_generation(item, inode->i_generation);
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
+ int ret = 0;
+
+ if (wait) {
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, inode);
+ ret = btrfs_commit_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ }
+ return ret;
+}
+
+static void btrfs_dirty_inode(struct inode *inode)
+{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_trans_handle *trans;
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, inode);
+ btrfs_update_inode(trans, root, inode);
+ btrfs_end_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ btrfs_btree_balance_dirty(root);
}
static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
- struct inode *dir, int mode)
+ struct btrfs_root *root,
+ u64 objectid,
+ struct btrfs_block_group_cache *group,
+ int mode)
{
struct inode *inode;
struct btrfs_inode_item inode_item;
- struct btrfs_root *root = btrfs_sb(dir->i_sb);
- struct btrfs_key key;
+ struct btrfs_key *location;
int ret;
- u64 objectid;
+ int owner;
- inode = new_inode(dir->i_sb);
+ inode = new_inode(root->fs_info->sb);
if (!inode)
return ERR_PTR(-ENOMEM);
- ret = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
- BUG_ON(ret);
+ BTRFS_I(inode)->root = root;
+ if (mode & S_IFDIR)
+ owner = 0;
+ else
+ owner = 1;
+ group = btrfs_find_block_group(root, group, 0, 0, owner);
+ BTRFS_I(inode)->block_group = group;
inode->i_uid = current->fsuid;
inode->i_gid = current->fsgid;
inode->i_mode = mode;
inode->i_ino = objectid;
inode->i_blocks = 0;
- inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
+ inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
fill_inode_item(&inode_item, inode);
-
-
- key.objectid = objectid;
- key.flags = 0;
- key.offset = 0;
- btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
- ret = btrfs_insert_inode_map(trans, root, objectid, &key);
- BUG_ON(ret);
+ location = &BTRFS_I(inode)->location;
+ location->objectid = objectid;
+ location->flags = 0;
+ location->offset = 0;
+ btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
BUG_ON(ret);
insert_inode_hash(inode);
- // FIXME mark_inode_dirty(inode)
return inode;
}
+static inline u8 btrfs_inode_type(struct inode *inode)
+{
+ return btrfs_type_by_mode[(inode->i_mode & S_IFMT) >> S_SHIFT];
+}
+
static int btrfs_add_link(struct btrfs_trans_handle *trans,
struct dentry *dentry, struct inode *inode)
{
int ret;
- ret = btrfs_insert_dir_item(trans, btrfs_sb(inode->i_sb),
+ struct btrfs_key key;
+ struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
+ key.objectid = inode->i_ino;
+ key.flags = 0;
+ btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
+ key.offset = 0;
+
+ ret = btrfs_insert_dir_item(trans, root,
dentry->d_name.name, dentry->d_name.len,
dentry->d_parent->d_inode->i_ino,
- inode->i_ino, 0);
+ &key, btrfs_inode_type(inode));
+ if (ret == 0) {
+ dentry->d_parent->d_inode->i_size += dentry->d_name.len * 2;
+ ret = btrfs_update_inode(trans, root,
+ dentry->d_parent->d_inode);
+ }
return ret;
}
d_instantiate(dentry, inode);
return 0;
}
+ if (err > 0)
+ err = -EEXIST;
return err;
}
int mode, struct nameidata *nd)
{
struct btrfs_trans_handle *trans;
- struct btrfs_root *root = btrfs_sb(dir->i_sb);
+ struct btrfs_root *root = BTRFS_I(dir)->root;
struct inode *inode;
int err;
int drop_inode = 0;
+ u64 objectid;
mutex_lock(&root->fs_info->fs_mutex);
trans = btrfs_start_transaction(root, 1);
- inode = btrfs_new_inode(trans, dir, mode);
+ btrfs_set_trans_block_group(trans, dir);
+
+ err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
+ if (err) {
+ err = -ENOSPC;
+ goto out_unlock;
+ }
+
+ inode = btrfs_new_inode(trans, root, objectid,
+ BTRFS_I(dir)->block_group, mode);
err = PTR_ERR(inode);
if (IS_ERR(inode))
goto out_unlock;
- // FIXME mark the inode dirty
+
+ btrfs_set_trans_block_group(trans, inode);
err = btrfs_add_nondir(trans, dentry, inode);
if (err)
drop_inode = 1;
+ else {
+ inode->i_mapping->a_ops = &btrfs_aops;
+ inode->i_fop = &btrfs_file_operations;
+ inode->i_op = &btrfs_file_inode_operations;
+ }
dir->i_sb->s_dirt = 1;
- btrfs_end_transaction(trans, root);
+ btrfs_update_inode_block_group(trans, inode);
+ btrfs_update_inode_block_group(trans, dir);
out_unlock:
+ btrfs_end_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+
+ if (drop_inode) {
+ inode_dec_link_count(inode);
+ iput(inode);
+ }
+ btrfs_btree_balance_dirty(root);
+ return err;
+}
+
+static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *dentry)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *root = BTRFS_I(dir)->root;
+ struct inode *inode = old_dentry->d_inode;
+ int err;
+ int drop_inode = 0;
+
+ if (inode->i_nlink == 0)
+ return -ENOENT;
+
+ inc_nlink(inode);
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, dir);
+ atomic_inc(&inode->i_count);
+ err = btrfs_add_nondir(trans, dentry, inode);
+ if (err)
+ drop_inode = 1;
+ dir->i_sb->s_dirt = 1;
+ btrfs_update_inode_block_group(trans, dir);
+ btrfs_update_inode(trans, root, inode);
+
+ btrfs_end_transaction(trans, root);
mutex_unlock(&root->fs_info->fs_mutex);
+
if (drop_inode) {
inode_dec_link_count(inode);
iput(inode);
}
+ btrfs_btree_balance_dirty(root);
+ return err;
+}
+
+static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 objectid, u64 dirid)
+{
+ int ret;
+ char buf[2];
+ struct btrfs_key key;
+
+ buf[0] = '.';
+ buf[1] = '.';
+
+ key.objectid = objectid;
+ key.offset = 0;
+ key.flags = 0;
+ btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
+
+ ret = btrfs_insert_dir_item(trans, root, buf, 1, objectid,
+ &key, BTRFS_FT_DIR);
+ if (ret)
+ goto error;
+ key.objectid = dirid;
+ ret = btrfs_insert_dir_item(trans, root, buf, 2, objectid,
+ &key, BTRFS_FT_DIR);
+ if (ret)
+ goto error;
+error:
+ return ret;
+}
+
+static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
+{
+ struct inode *inode;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *root = BTRFS_I(dir)->root;
+ int err = 0;
+ int drop_on_err = 0;
+ u64 objectid;
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, dir);
+ if (IS_ERR(trans)) {
+ err = PTR_ERR(trans);
+ goto out_unlock;
+ }
+
+ err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
+ if (err) {
+ err = -ENOSPC;
+ goto out_unlock;
+ }
+
+ inode = btrfs_new_inode(trans, root, objectid,
+ BTRFS_I(dir)->block_group, S_IFDIR | mode);
+ if (IS_ERR(inode)) {
+ err = PTR_ERR(inode);
+ goto out_fail;
+ }
+ drop_on_err = 1;
+ inode->i_op = &btrfs_dir_inode_operations;
+ inode->i_fop = &btrfs_dir_file_operations;
+ btrfs_set_trans_block_group(trans, inode);
+
+ err = btrfs_make_empty_dir(trans, root, inode->i_ino, dir->i_ino);
+ if (err)
+ goto out_fail;
+
+ inode->i_size = 6;
+ err = btrfs_update_inode(trans, root, inode);
+ if (err)
+ goto out_fail;
+ err = btrfs_add_link(trans, dentry, inode);
+ if (err)
+ goto out_fail;
+ d_instantiate(dentry, inode);
+ drop_on_err = 0;
+ dir->i_sb->s_dirt = 1;
+ btrfs_update_inode_block_group(trans, inode);
+ btrfs_update_inode_block_group(trans, dir);
+
+out_fail:
+ btrfs_end_transaction(trans, root);
+out_unlock:
+ mutex_unlock(&root->fs_info->fs_mutex);
+ if (drop_on_err)
+ iput(inode);
+ btrfs_btree_balance_dirty(root);
return err;
}
+static int btrfs_sync_file(struct file *file,
+ struct dentry *dentry, int datasync)
+{
+ struct inode *inode = dentry->d_inode;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ int ret;
+ struct btrfs_trans_handle *trans;
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ if (!trans) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ ret = btrfs_commit_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+out:
+ return ret > 0 ? EIO : ret;
+}
+
static int btrfs_sync_fs(struct super_block *sb, int wait)
{
struct btrfs_trans_handle *trans;
struct btrfs_root *root;
int ret;
+ root = btrfs_sb(sb);
sb->s_dirt = 0;
if (!wait) {
- filemap_flush(sb->s_bdev->bd_inode->i_mapping);
+ filemap_flush(root->fs_info->btree_inode->i_mapping);
return 0;
}
- filemap_write_and_wait(sb->s_bdev->bd_inode->i_mapping);
-
- root = btrfs_sb(sb);
mutex_lock(&root->fs_info->fs_mutex);
trans = btrfs_start_transaction(root, 1);
ret = btrfs_commit_transaction(trans, root);
return 0;
}
+#define BTRFS_GET_BLOCK_NO_CREATE 0
+#define BTRFS_GET_BLOCK_CREATE 1
+#define BTRFS_GET_BLOCK_NO_DIRECT 2
+
+static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
+ struct buffer_head *result, int create)
+{
+ int ret;
+ int err = 0;
+ u64 blocknr;
+ u64 extent_start = 0;
+ u64 extent_end = 0;
+ u64 objectid = inode->i_ino;
+ u32 found_type;
+ u64 alloc_hint = 0;
+ struct btrfs_path *path;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_file_extent_item *item;
+ struct btrfs_leaf *leaf;
+ struct btrfs_disk_key *found_key;
+ struct btrfs_trans_handle *trans = NULL;
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ btrfs_init_path(path);
+ if (create & BTRFS_GET_BLOCK_CREATE) {
+ WARN_ON(1);
+ /* this almost but not quite works */
+ trans = btrfs_start_transaction(root, 1);
+ if (!trans) {
+ err = -ENOMEM;
+ goto out;
+ }
+ ret = drop_extents(trans, root, inode,
+ iblock << inode->i_blkbits,
+ (iblock + 1) << inode->i_blkbits,
+ &alloc_hint);
+ BUG_ON(ret);
+ }
+
+ ret = btrfs_lookup_file_extent(NULL, root, path,
+ inode->i_ino,
+ iblock << inode->i_blkbits, 0);
+ if (ret < 0) {
+ err = ret;
+ goto out;
+ }
+
+ if (ret != 0) {
+ if (path->slots[0] == 0) {
+ btrfs_release_path(root, path);
+ goto not_found;
+ }
+ path->slots[0]--;
+ }
+
+ item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
+ struct btrfs_file_extent_item);
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ blocknr = btrfs_file_extent_disk_blocknr(item);
+ blocknr += btrfs_file_extent_offset(item);
+
+ /* are we inside the extent that was found? */
+ found_key = &leaf->items[path->slots[0]].key;
+ found_type = btrfs_disk_key_type(found_key);
+ if (btrfs_disk_key_objectid(found_key) != objectid ||
+ found_type != BTRFS_EXTENT_DATA_KEY) {
+ extent_end = 0;
+ extent_start = 0;
+ goto not_found;
+ }
+ found_type = btrfs_file_extent_type(item);
+ extent_start = btrfs_disk_key_offset(&leaf->items[path->slots[0]].key);
+ 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 (btrfs_file_extent_disk_blocknr(item) == 0)
+ goto out;
+ if (iblock >= extent_start && iblock < extent_end) {
+ btrfs_map_bh_to_logical(root, result, blocknr +
+ iblock - extent_start);
+ goto out;
+ }
+ } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
+ char *ptr;
+ char *map;
+ u32 size;
+
+ if (create & BTRFS_GET_BLOCK_NO_DIRECT) {
+ err = -EINVAL;
+ goto out;
+ }
+ size = btrfs_file_extent_inline_len(leaf->items +
+ path->slots[0]);
+ extent_end = (extent_start + size) >> inode->i_blkbits;
+ extent_start >>= inode->i_blkbits;
+ if (iblock < extent_start || iblock > extent_end) {
+ goto not_found;
+ }
+ ptr = btrfs_file_extent_inline_start(item);
+ map = kmap(result->b_page);
+ memcpy(map, ptr, size);
+ memset(map + size, 0, PAGE_CACHE_SIZE - size);
+ flush_dcache_page(result->b_page);
+ kunmap(result->b_page);
+ set_buffer_uptodate(result);
+ SetPageChecked(result->b_page);
+ btrfs_map_bh_to_logical(root, result, 0);
+ }
+not_found:
+ if (create & BTRFS_GET_BLOCK_CREATE) {
+ struct btrfs_key ins;
+ ret = btrfs_alloc_extent(trans, root, inode->i_ino,
+ 1, alloc_hint, (u64)-1,
+ &ins, 1);
+ BUG_ON(ret);
+ ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
+ iblock << inode->i_blkbits,
+ ins.objectid, ins.offset,
+ ins.offset);
+ BUG_ON(ret);
+ SetPageChecked(result->b_page);
+ btrfs_map_bh_to_logical(root, result, ins.objectid);
+ }
+out:
+ if (trans)
+ err = btrfs_end_transaction(trans, root);
+ btrfs_free_path(path);
+ return err;
+}
+
+static int btrfs_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *result, int create)
+{
+ int err;
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ mutex_lock(&root->fs_info->fs_mutex);
+ err = btrfs_get_block_lock(inode, iblock, result, create);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ return err;
+}
+
+static int btrfs_get_block_bmap(struct inode *inode, sector_t iblock,
+ struct buffer_head *result, int create)
+{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ mutex_lock(&root->fs_info->fs_mutex);
+ btrfs_get_block_lock(inode, iblock, result, BTRFS_GET_BLOCK_NO_DIRECT);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ return 0;
+}
+
+static sector_t btrfs_bmap(struct address_space *as, sector_t block)
+{
+ return generic_block_bmap(as, block, btrfs_get_block_bmap);
+}
+
+static int btrfs_prepare_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ return block_prepare_write(page, from, to, btrfs_get_block);
+}
+
static void btrfs_write_super(struct super_block *sb)
{
btrfs_sync_fs(sb, 1);
}
-
-static int btrfs_get_sb(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data, struct vfsmount *mnt)
+static int btrfs_readpage(struct file *file, struct page *page)
{
- return get_sb_bdev(fs_type, flags, dev_name, data,
- btrfs_fill_super, mnt);
+ return mpage_readpage(page, btrfs_get_block);
}
-static struct file_system_type btrfs_fs_type = {
- .owner = THIS_MODULE,
- .name = "btrfs",
- .get_sb = btrfs_get_sb,
- .kill_sb = kill_block_super,
- .fs_flags = FS_REQUIRES_DEV,
-};
+/*
+ * While block_write_full_page is writing back the dirty buffers under
+ * the page lock, whoever dirtied the buffers may decide to clean them
+ * again at any time. We handle that by only looking at the buffer
+ * state inside lock_buffer().
+ *
+ * If block_write_full_page() is called for regular writeback
+ * (wbc->sync_mode == WB_SYNC_NONE) then it will redirty a page which has a
+ * locked buffer. This only can happen if someone has written the buffer
+ * directly, with submit_bh(). At the address_space level PageWriteback
+ * prevents this contention from occurring.
+ */
+static int __btrfs_write_full_page(struct inode *inode, struct page *page,
+ struct writeback_control *wbc)
+{
+ int err;
+ sector_t block;
+ sector_t last_block;
+ struct buffer_head *bh, *head;
+ const unsigned blocksize = 1 << inode->i_blkbits;
+ int nr_underway = 0;
-static struct super_operations btrfs_super_ops = {
- .statfs = simple_statfs,
- .delete_inode = btrfs_delete_inode,
- .put_super = btrfs_put_super,
- .read_inode = btrfs_read_locked_inode,
- .write_super = btrfs_write_super,
- .sync_fs = btrfs_sync_fs,
-};
+ BUG_ON(!PageLocked(page));
-static struct inode_operations btrfs_dir_inode_operations = {
- .lookup = btrfs_lookup,
- .create = btrfs_create,
- .unlink = btrfs_unlink,
-};
+ last_block = (i_size_read(inode) - 1) >> inode->i_blkbits;
-static struct file_operations btrfs_dir_file_operations = {
- .llseek = generic_file_llseek,
- .read = generic_read_dir,
- .readdir = btrfs_readdir,
-};
+ if (!page_has_buffers(page)) {
+ create_empty_buffers(page, blocksize,
+ (1 << BH_Dirty)|(1 << BH_Uptodate));
+ }
+ /*
+ * Be very careful. We have no exclusion from __set_page_dirty_buffers
+ * here, and the (potentially unmapped) buffers may become dirty at
+ * any time. If a buffer becomes dirty here after we've inspected it
+ * then we just miss that fact, and the page stays dirty.
+ *
+ * Buffers outside i_size may be dirtied by __set_page_dirty_buffers;
+ * handle that here by just cleaning them.
+ */
+
+ block = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ head = page_buffers(page);
+ bh = head;
+
+ /*
+ * Get all the dirty buffers mapped to disk addresses and
+ * handle any aliases from the underlying blockdev's mapping.
+ */
+ do {
+ if (block > last_block) {
+ /*
+ * mapped buffers outside i_size will occur, because
+ * this page can be outside i_size when there is a
+ * truncate in progress.
+ */
+ /*
+ * The buffer was zeroed by block_write_full_page()
+ */
+ clear_buffer_dirty(bh);
+ set_buffer_uptodate(bh);
+ } else if (!buffer_mapped(bh) && buffer_dirty(bh)) {
+ WARN_ON(bh->b_size != blocksize);
+ err = btrfs_get_block(inode, block, bh, 0);
+ if (err) {
+printk("writepage going to recovery err %d\n", err);
+ goto recover;
+ }
+ if (buffer_new(bh)) {
+ /* blockdev mappings never come here */
+ clear_buffer_new(bh);
+ }
+ }
+ bh = bh->b_this_page;
+ block++;
+ } while (bh != head);
-static int __init init_btrfs_fs(void)
-{
- printk("btrfs loaded!\n");
+ do {
+ if (!buffer_mapped(bh))
+ continue;
+ /*
+ * If it's a fully non-blocking write attempt and we cannot
+ * lock the buffer then redirty the page. Note that this can
+ * potentially cause a busy-wait loop from pdflush and kswapd
+ * activity, but those code paths have their own higher-level
+ * throttling.
+ */
+ if (wbc->sync_mode != WB_SYNC_NONE || !wbc->nonblocking) {
+ lock_buffer(bh);
+ } else if (test_set_buffer_locked(bh)) {
+ redirty_page_for_writepage(wbc, page);
+ continue;
+ }
+ if (test_clear_buffer_dirty(bh) && bh->b_blocknr != 0) {
+ mark_buffer_async_write(bh);
+ } else {
+ unlock_buffer(bh);
+ }
+ } while ((bh = bh->b_this_page) != head);
+
+ /*
+ * The page and its buffers are protected by PageWriteback(), so we can
+ * drop the bh refcounts early.
+ */
+ BUG_ON(PageWriteback(page));
+ set_page_writeback(page);
+
+ do {
+ struct buffer_head *next = bh->b_this_page;
+ if (buffer_async_write(bh)) {
+ submit_bh(WRITE, bh);
+ nr_underway++;
+ }
+ bh = next;
+ } while (bh != head);
+ unlock_page(page);
+
+ err = 0;
+done:
+ if (nr_underway == 0) {
+ /*
+ * The page was marked dirty, but the buffers were
+ * clean. Someone wrote them back by hand with
+ * ll_rw_block/submit_bh. A rare case.
+ */
+ int uptodate = 1;
+ do {
+ if (!buffer_uptodate(bh)) {
+ uptodate = 0;
+ break;
+ }
+ bh = bh->b_this_page;
+ } while (bh != head);
+ if (uptodate)
+ SetPageUptodate(page);
+ end_page_writeback(page);
+ }
+ return err;
+
+recover:
+ /*
+ * ENOSPC, or some other error. We may already have added some
+ * blocks to the file, so we need to write these out to avoid
+ * exposing stale data.
+ * The page is currently locked and not marked for writeback
+ */
+ bh = head;
+ /* Recovery: lock and submit the mapped buffers */
+ do {
+ if (buffer_mapped(bh) && buffer_dirty(bh)) {
+ lock_buffer(bh);
+ mark_buffer_async_write(bh);
+ } else {
+ /*
+ * The buffer may have been set dirty during
+ * attachment to a dirty page.
+ */
+ clear_buffer_dirty(bh);
+ }
+ } while ((bh = bh->b_this_page) != head);
+ SetPageError(page);
+ BUG_ON(PageWriteback(page));
+ set_page_writeback(page);
+ do {
+ struct buffer_head *next = bh->b_this_page;
+ if (buffer_async_write(bh)) {
+ clear_buffer_dirty(bh);
+ submit_bh(WRITE, bh);
+ nr_underway++;
+ }
+ bh = next;
+ } while (bh != head);
+ unlock_page(page);
+ goto done;
+}
+
+/*
+ * The generic ->writepage function for buffer-backed address_spaces
+ */
+static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
+{
+ struct inode * const inode = page->mapping->host;
+ loff_t i_size = i_size_read(inode);
+ const pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
+ unsigned offset;
+ void *kaddr;
+
+ /* Is the page fully inside i_size? */
+ if (page->index < end_index)
+ return __btrfs_write_full_page(inode, page, wbc);
+
+ /* Is the page fully outside i_size? (truncate in progress) */
+ offset = i_size & (PAGE_CACHE_SIZE-1);
+ if (page->index >= end_index+1 || !offset) {
+ /*
+ * The page may have dirty, unmapped buffers. For example,
+ * they may have been added in ext3_writepage(). Make them
+ * freeable here, so the page does not leak.
+ */
+ block_invalidatepage(page, 0);
+ unlock_page(page);
+ return 0; /* don't care */
+ }
+
+ /*
+ * The page straddles i_size. It must be zeroed out on each and every
+ * writepage invokation because it may be mmapped. "A file is mapped
+ * in multiples of the page size. For a file that is not a multiple of
+ * the page size, the remaining memory is zeroed when mapped, and
+ * writes to that region are not written out to the file."
+ */
+ kaddr = kmap_atomic(page, KM_USER0);
+ memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
+ flush_dcache_page(page);
+ kunmap_atomic(kaddr, KM_USER0);
+ return __btrfs_write_full_page(inode, page, wbc);
+}
+
+static void btrfs_truncate(struct inode *inode)
+{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ int ret;
+ struct btrfs_trans_handle *trans;
+
+ if (!S_ISREG(inode->i_mode))
+ return;
+ if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+ return;
+
+ btrfs_truncate_page(inode->i_mapping, inode->i_size);
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, inode);
+
+ /* FIXME, add redo link to tree so we don't leak on crash */
+ ret = btrfs_truncate_in_trans(trans, root, inode);
+ BUG_ON(ret);
+ btrfs_update_inode(trans, root, inode);
+ ret = btrfs_end_transaction(trans, root);
+ BUG_ON(ret);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ btrfs_btree_balance_dirty(root);
+}
+
+static int btrfs_commit_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ struct inode *inode = page->mapping->host;
+ struct buffer_head *bh;
+ loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+
+ SetPageUptodate(page);
+ bh = page_buffers(page);
+ set_buffer_uptodate(bh);
+ if (buffer_mapped(bh) && bh->b_blocknr != 0) {
+ set_page_dirty(page);
+ }
+ if (pos > inode->i_size) {
+ i_size_write(inode, pos);
+ mark_inode_dirty(inode);
+ }
+ return 0;
+}
+
+static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
+ struct page **prepared_pages,
+ const char __user * buf)
+{
+ long page_fault = 0;
+ int i;
+ int offset = pos & (PAGE_CACHE_SIZE - 1);
+
+ for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) {
+ size_t count = min_t(size_t,
+ PAGE_CACHE_SIZE - offset, write_bytes);
+ struct page *page = prepared_pages[i];
+ fault_in_pages_readable(buf, count);
+
+ /* Copy data from userspace to the current page */
+ kmap(page);
+ page_fault = __copy_from_user(page_address(page) + offset,
+ buf, count);
+ /* Flush processor's dcache for this page */
+ flush_dcache_page(page);
+ kunmap(page);
+ buf += count;
+ write_bytes -= count;
+
+ if (page_fault)
+ break;
+ }
+ return page_fault ? -EFAULT : 0;
+}
+
+static void btrfs_drop_pages(struct page **pages, size_t num_pages)
+{
+ size_t i;
+ for (i = 0; i < num_pages; i++) {
+ if (!pages[i])
+ break;
+ unlock_page(pages[i]);
+ mark_page_accessed(pages[i]);
+ page_cache_release(pages[i]);
+ }
+}
+static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct file *file,
+ struct page **pages,
+ size_t num_pages,
+ loff_t pos,
+ size_t write_bytes)
+{
+ int i;
+ int offset;
+ int err = 0;
+ int ret;
+ int this_write;
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct buffer_head *bh;
+ struct btrfs_file_extent_item *ei;
+
+ for (i = 0; i < num_pages; i++) {
+ offset = pos & (PAGE_CACHE_SIZE -1);
+ this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
+ /* FIXME, one block at a time */
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, inode);
+
+ bh = page_buffers(pages[i]);
+ if (buffer_mapped(bh) && bh->b_blocknr == 0) {
+ struct btrfs_key key;
+ struct btrfs_path *path;
+ char *ptr;
+ u32 datasize;
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ key.objectid = inode->i_ino;
+ key.offset = pages[i]->index << PAGE_CACHE_SHIFT;
+ key.flags = 0;
+ btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
+ BUG_ON(write_bytes >= PAGE_CACHE_SIZE);
+ datasize = offset +
+ btrfs_file_extent_calc_inline_size(write_bytes);
+ ret = btrfs_insert_empty_item(trans, root, path, &key,
+ datasize);
+ BUG_ON(ret);
+ ei = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+ path->slots[0], struct btrfs_file_extent_item);
+ btrfs_set_file_extent_generation(ei, trans->transid);
+ btrfs_set_file_extent_type(ei,
+ BTRFS_FILE_EXTENT_INLINE);
+ ptr = btrfs_file_extent_inline_start(ei);
+ btrfs_memcpy(root, path->nodes[0]->b_data,
+ ptr, bh->b_data, offset + write_bytes);
+ mark_buffer_dirty(path->nodes[0]);
+ btrfs_free_path(path);
+ } 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);
+ kunmap(pages[i]);
+ }
+ SetPageChecked(pages[i]);
+ // btrfs_update_inode_block_group(trans, inode);
+ ret = btrfs_end_transaction(trans, root);
+ BUG_ON(ret);
+ mutex_unlock(&root->fs_info->fs_mutex);
+
+ ret = btrfs_commit_write(file, pages[i], offset,
+ offset + this_write);
+ pos += this_write;
+ if (ret) {
+ err = ret;
+ goto failed;
+ }
+ WARN_ON(this_write > write_bytes);
+ write_bytes -= this_write;
+ }
+failed:
+ return err;
+}
+
+static int drop_extents(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct inode *inode,
+ u64 start, u64 end, u64 *hint_block)
+{
+ int ret;
+ struct btrfs_key key;
+ struct btrfs_leaf *leaf;
+ int slot;
+ struct btrfs_file_extent_item *extent;
+ u64 extent_end = 0;
+ int keep;
+ struct btrfs_file_extent_item old;
+ struct btrfs_path *path;
+ u64 search_start = start;
+ int bookend;
+ int found_type;
+ int found_extent;
+ int found_inline;
+
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ 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 = 0;
+ goto out;
+ }
+ path->slots[0]--;
+ }
+ keep = 0;
+ bookend = 0;
+ found_extent = 0;
+ found_inline = 0;
+ extent = NULL;
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ slot = path->slots[0];
+ btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
+ if (key.offset >= end || key.objectid != inode->i_ino) {
+ ret = 0;
+ goto out;
+ }
+ if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) {
+ ret = 0;
+ goto out;
+ }
+ extent = btrfs_item_ptr(leaf, slot,
+ struct btrfs_file_extent_item);
+ found_type = btrfs_file_extent_type(extent);
+ if (found_type == BTRFS_FILE_EXTENT_REG) {
+ extent_end = key.offset +
+ (btrfs_file_extent_num_blocks(extent) <<
+ inode->i_blkbits);
+ found_extent = 1;
+ } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
+ found_inline = 1;
+ extent_end = key.offset +
+ btrfs_file_extent_inline_len(leaf->items + slot);
+ }
+
+ if (!found_extent && !found_inline) {
+ ret = 0;
+ goto out;
+ }
+
+ if (search_start >= extent_end) {
+ ret = 0;
+ goto out;
+ }
+
+ 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));
+ 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;
+ }
+
+ if (start > key.offset) {
+ u64 new_num;
+ u64 old_num;
+ /* truncate existing extent */
+ keep = 1;
+ WARN_ON(start & (root->blocksize - 1));
+ if (found_extent) {
+ new_num = (start - key.offset) >>
+ inode->i_blkbits;
+ old_num = btrfs_file_extent_num_blocks(extent);
+ *hint_block =
+ btrfs_file_extent_disk_blocknr(extent);
+ 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]);
+ } else {
+ WARN_ON(1);
+ }
+ }
+ if (!keep) {
+ u64 disk_blocknr = 0;
+ u64 disk_num_blocks = 0;
+ u64 extent_num_blocks = 0;
+ if (found_extent) {
+ disk_blocknr =
+ btrfs_file_extent_disk_blocknr(extent);
+ disk_num_blocks =
+ btrfs_file_extent_disk_num_blocks(extent);
+ extent_num_blocks =
+ btrfs_file_extent_num_blocks(extent);
+ *hint_block =
+ btrfs_file_extent_disk_blocknr(extent);
+ }
+ ret = btrfs_del_item(trans, root, path);
+ BUG_ON(ret);
+ btrfs_release_path(root, path);
+ extent = NULL;
+ if (found_extent && disk_blocknr != 0) {
+ inode->i_blocks -= extent_num_blocks << 3;
+ 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)
+ continue;
+ }
+ if (bookend && found_extent) {
+ /* create bookend */
+ struct btrfs_key ins;
+ 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 = 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) <
+ (extent_end - end) >> inode->i_blkbits);
+ btrfs_set_file_extent_num_blocks(extent,
+ (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]);
+ if (btrfs_file_extent_disk_blocknr(&old) != 0) {
+ inode->i_blocks +=
+ btrfs_file_extent_num_blocks(extent) << 3;
+ }
+ ret = 0;
+ goto out;
+ }
+ }
+out:
+ btrfs_free_path(path);
+ return ret;
+}
+
+static int prepare_pages(struct btrfs_root *root,
+ struct file *file,
+ struct page **pages,
+ size_t num_pages,
+ loff_t pos,
+ unsigned long first_index,
+ unsigned long last_index,
+ size_t write_bytes,
+ u64 alloc_extent_start)
+{
+ int i;
+ unsigned long index = pos >> PAGE_CACHE_SHIFT;
+ struct inode *inode = file->f_path.dentry->d_inode;
+ int offset;
+ int err = 0;
+ int this_write;
+ struct buffer_head *bh;
+ struct buffer_head *head;
+ loff_t isize = i_size_read(inode);
+
+ memset(pages, 0, num_pages * sizeof(struct page *));
+
+ for (i = 0; i < num_pages; i++) {
+ pages[i] = grab_cache_page(inode->i_mapping, index + i);
+ if (!pages[i]) {
+ err = -ENOMEM;
+ goto failed_release;
+ }
+ cancel_dirty_page(pages[i], PAGE_CACHE_SIZE);
+ wait_on_page_writeback(pages[i]);
+ offset = pos & (PAGE_CACHE_SIZE -1);
+ this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
+ if (!page_has_buffers(pages[i])) {
+ create_empty_buffers(pages[i],
+ root->fs_info->sb->s_blocksize,
+ (1 << BH_Uptodate));
+ }
+ head = page_buffers(pages[i]);
+ bh = head;
+ do {
+ err = btrfs_map_bh_to_logical(root, bh,
+ alloc_extent_start);
+ BUG_ON(err);
+ if (err)
+ goto failed_truncate;
+ bh = bh->b_this_page;
+ if (alloc_extent_start)
+ alloc_extent_start++;
+ } while (bh != head);
+ pos += this_write;
+ WARN_ON(this_write > write_bytes);
+ write_bytes -= this_write;
+ }
+ return 0;
+
+failed_release:
+ btrfs_drop_pages(pages, num_pages);
+ return err;
+
+failed_truncate:
+ btrfs_drop_pages(pages, num_pages);
+ if (pos > isize)
+ vmtruncate(inode, isize);
+ return err;
+}
+
+static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ loff_t pos;
+ size_t num_written = 0;
+ int err = 0;
+ int ret = 0;
+ 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];
+ unsigned long first_index;
+ unsigned long last_index;
+ u64 start_pos;
+ u64 num_blocks;
+ u64 alloc_extent_start;
+ u64 hint_block;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_key ins;
+ pinned[0] = NULL;
+ pinned[1] = NULL;
+ if (file->f_flags & O_DIRECT)
+ return -EINVAL;
+ pos = *ppos;
+ 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));
+ if (err)
+ goto out;
+ if (count == 0)
+ goto out;
+ err = remove_suid(file->f_path.dentry);
+ 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 ((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);
+ wait_on_page_locked(pinned[0]);
+ } else {
+ unlock_page(pinned[0]);
+ }
+ }
+ if ((pos + 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);
+ wait_on_page_locked(pinned[1]);
+ } else {
+ unlock_page(pinned[1]);
+ }
+ }
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ if (!trans) {
+ err = -ENOMEM;
+ mutex_unlock(&root->fs_info->fs_mutex);
+ goto out_unlock;
+ }
+ btrfs_set_trans_block_group(trans, inode);
+ /* FIXME blocksize != 4096 */
+ inode->i_blocks += num_blocks << 3;
+ hint_block = 0;
+ if (start_pos < inode->i_size) {
+ /* FIXME blocksize != pagesize */
+ ret = drop_extents(trans, root, inode,
+ start_pos,
+ (pos + count + root->blocksize -1) &
+ ~((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,
+ num_blocks, hint_block, (u64)-1,
+ &ins, 1);
+ BUG_ON(ret);
+ ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
+ start_pos, ins.objectid, ins.offset,
+ ins.offset);
+ BUG_ON(ret);
+ } else {
+ ins.offset = 0;
+ ins.objectid = 0;
+ }
+ BUG_ON(ret);
+ alloc_extent_start = ins.objectid;
+ // btrfs_update_inode_block_group(trans, inode);
+ ret = btrfs_end_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+
+ while(count > 0) {
+ size_t offset = pos & (PAGE_CACHE_SIZE - 1);
+ size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
+ size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
+ PAGE_CACHE_SHIFT;
+
+ 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 */
+ if (alloc_extent_start)
+ alloc_extent_start += num_pages;
+ ret = btrfs_copy_from_user(pos, num_pages,
+ write_bytes, pages, buf);
+ BUG_ON(ret);
+
+ ret = dirty_and_release_pages(NULL, root, file, pages,
+ num_pages, pos, write_bytes);
+ BUG_ON(ret);
+ btrfs_drop_pages(pages, num_pages);
+
+ buf += write_bytes;
+ count -= write_bytes;
+ pos += write_bytes;
+ num_written += write_bytes;
+
+ balance_dirty_pages_ratelimited(inode->i_mapping);
+ btrfs_btree_balance_dirty(root);
+ cond_resched();
+ }
+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;
+}
+
+static int btrfs_read_actor(read_descriptor_t *desc, struct page *page,
+ unsigned long offset, unsigned long size)
+{
+ char *kaddr;
+ unsigned long left, count = desc->count;
+ struct inode *inode = page->mapping->host;
+
+ if (size > count)
+ size = count;
+
+ if (!PageChecked(page)) {
+ /* FIXME, do it per block */
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ int ret;
+ struct buffer_head *bh;
+
+ if (page_has_buffers(page)) {
+ bh = page_buffers(page);
+ if (!buffer_mapped(bh)) {
+ SetPageChecked(page);
+ goto checked;
+ }
+ }
+
+ ret = btrfs_csum_verify_file_block(root,
+ page->mapping->host->i_ino,
+ page->index << PAGE_CACHE_SHIFT,
+ kmap(page), PAGE_CACHE_SIZE);
+ if (ret) {
+ if (ret != -ENOENT) {
+ printk("failed to verify ino %lu page %lu ret %d\n",
+ page->mapping->host->i_ino,
+ page->index, ret);
+ memset(page_address(page), 1, PAGE_CACHE_SIZE);
+ flush_dcache_page(page);
+ }
+ }
+ SetPageChecked(page);
+ kunmap(page);
+ }
+checked:
+ /*
+ * Faults on the destination of a read are common, so do it before
+ * taking the kmap.
+ */
+ if (!fault_in_pages_writeable(desc->arg.buf, size)) {
+ kaddr = kmap_atomic(page, KM_USER0);
+ left = __copy_to_user_inatomic(desc->arg.buf,
+ kaddr + offset, size);
+ kunmap_atomic(kaddr, KM_USER0);
+ if (left == 0)
+ goto success;
+ }
+
+ /* Do it the slow way */
+ kaddr = kmap(page);
+ left = __copy_to_user(desc->arg.buf, kaddr + offset, size);
+ kunmap(page);
+
+ if (left) {
+ size -= left;
+ desc->error = -EFAULT;
+ }
+success:
+ desc->count = count - size;
+ desc->written += size;
+ desc->arg.buf += size;
+ return size;
+}
+
+/**
+ * btrfs_file_aio_read - filesystem read routine
+ * @iocb: kernel I/O control block
+ * @iov: io vector request
+ * @nr_segs: number of segments in the iovec
+ * @pos: current file position
+ */
+static ssize_t btrfs_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
+ unsigned long nr_segs, loff_t pos)
+{
+ struct file *filp = iocb->ki_filp;
+ ssize_t retval;
+ unsigned long seg;
+ size_t count;
+ loff_t *ppos = &iocb->ki_pos;
+
+ count = 0;
+ for (seg = 0; seg < nr_segs; seg++) {
+ const struct iovec *iv = &iov[seg];
+
+ /*
+ * If any segment has a negative length, or the cumulative
+ * length ever wraps negative then return -EINVAL.
+ */
+ count += iv->iov_len;
+ if (unlikely((ssize_t)(count|iv->iov_len) < 0))
+ return -EINVAL;
+ if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
+ continue;
+ if (seg == 0)
+ return -EFAULT;
+ nr_segs = seg;
+ count -= iv->iov_len; /* This segment is no good */
+ break;
+ }
+ retval = 0;
+ if (count) {
+ for (seg = 0; seg < nr_segs; seg++) {
+ read_descriptor_t desc;
+
+ desc.written = 0;
+ desc.arg.buf = iov[seg].iov_base;
+ desc.count = iov[seg].iov_len;
+ if (desc.count == 0)
+ continue;
+ desc.error = 0;
+ do_generic_file_read(filp, ppos, &desc,
+ btrfs_read_actor);
+ retval += desc.written;
+ if (desc.error) {
+ retval = retval ?: desc.error;
+ break;
+ }
+ }
+ }
+ return retval;
+}
+
+static int create_subvol(struct btrfs_root *root, char *name, int namelen)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_key key;
+ struct btrfs_root_item root_item;
+ struct btrfs_inode_item *inode_item;
+ struct buffer_head *subvol;
+ struct btrfs_leaf *leaf;
+ struct btrfs_root *new_root;
+ struct inode *inode;
+ struct inode *dir;
+ int ret;
+ u64 objectid;
+ u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ BUG_ON(!trans);
+
+ subvol = btrfs_alloc_free_block(trans, root, 0);
+ if (subvol == NULL)
+ return -ENOSPC;
+ leaf = btrfs_buffer_leaf(subvol);
+ btrfs_set_header_nritems(&leaf->header, 0);
+ btrfs_set_header_level(&leaf->header, 0);
+ btrfs_set_header_blocknr(&leaf->header, bh_blocknr(subvol));
+ btrfs_set_header_generation(&leaf->header, trans->transid);
+ btrfs_set_header_owner(&leaf->header, root->root_key.objectid);
+ memcpy(leaf->header.fsid, root->fs_info->disk_super->fsid,
+ sizeof(leaf->header.fsid));
+ mark_buffer_dirty(subvol);
+
+ inode_item = &root_item.inode;
+ memset(inode_item, 0, sizeof(*inode_item));
+ btrfs_set_inode_generation(inode_item, 1);
+ btrfs_set_inode_size(inode_item, 3);
+ btrfs_set_inode_nlink(inode_item, 1);
+ btrfs_set_inode_nblocks(inode_item, 1);
+ btrfs_set_inode_mode(inode_item, S_IFDIR | 0755);
+
+ btrfs_set_root_blocknr(&root_item, bh_blocknr(subvol));
+ btrfs_set_root_refs(&root_item, 1);
+ brelse(subvol);
+ subvol = NULL;
+
+ ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
+ 0, &objectid);
+ BUG_ON(ret);
+
+ btrfs_set_root_dirid(&root_item, new_dirid);
+
+ key.objectid = objectid;
+ key.offset = 1;
+ key.flags = 0;
+ btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
+ ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
+ &root_item);
+ BUG_ON(ret);
+
+ /*
+ * insert the directory item
+ */
+ key.offset = (u64)-1;
+ dir = root->fs_info->sb->s_root->d_inode;
+ ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
+ name, namelen, dir->i_ino, &key,
+ BTRFS_FT_DIR);
+ BUG_ON(ret);
+
+ ret = btrfs_commit_transaction(trans, root);
+ BUG_ON(ret);
+
+ new_root = btrfs_read_fs_root(root->fs_info, &key);
+ BUG_ON(!new_root);
+
+ trans = btrfs_start_transaction(new_root, 1);
+ BUG_ON(!trans);
+
+ inode = btrfs_new_inode(trans, new_root, new_dirid,
+ BTRFS_I(dir)->block_group, S_IFDIR | 0700);
+ inode->i_op = &btrfs_dir_inode_operations;
+ inode->i_fop = &btrfs_dir_file_operations;
+
+ ret = btrfs_make_empty_dir(trans, new_root, new_dirid, new_dirid);
+ BUG_ON(ret);
+
+ inode->i_nlink = 1;
+ inode->i_size = 6;
+ ret = btrfs_update_inode(trans, new_root, inode);
+ BUG_ON(ret);
+
+ ret = btrfs_commit_transaction(trans, new_root);
+ BUG_ON(ret);
+
+ iput(inode);
+
+ mutex_unlock(&root->fs_info->fs_mutex);
+ btrfs_btree_balance_dirty(root);
+ return 0;
+}
+
+static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_key key;
+ struct btrfs_root_item new_root_item;
+ int ret;
+ u64 objectid;
+
+ if (!root->ref_cows)
+ return -EINVAL;
+
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ BUG_ON(!trans);
+
+ ret = btrfs_update_inode(trans, root, root->inode);
+ BUG_ON(ret);
+
+ ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
+ 0, &objectid);
+ BUG_ON(ret);
+
+ memcpy(&new_root_item, &root->root_item,
+ sizeof(new_root_item));
+
+ key.objectid = objectid;
+ key.offset = 1;
+ key.flags = 0;
+ btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
+ btrfs_set_root_blocknr(&new_root_item, bh_blocknr(root->node));
+
+ ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
+ &new_root_item);
+ BUG_ON(ret);
+
+ /*
+ * insert the directory item
+ */
+ key.offset = (u64)-1;
+ ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
+ name, namelen,
+ root->fs_info->sb->s_root->d_inode->i_ino,
+ &key, BTRFS_FT_DIR);
+
+ BUG_ON(ret);
+
+ ret = btrfs_inc_root_ref(trans, root);
+ BUG_ON(ret);
+
+ ret = btrfs_commit_transaction(trans, root);
+ BUG_ON(ret);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ btrfs_btree_balance_dirty(root);
+ return 0;
+}
+
+static int add_disk(struct btrfs_root *root, char *name, int namelen)
+{
+ struct block_device *bdev;
+ struct btrfs_path *path;
+ struct super_block *sb = root->fs_info->sb;
+ struct btrfs_root *dev_root = root->fs_info->dev_root;
+ struct btrfs_trans_handle *trans;
+ struct btrfs_device_item *dev_item;
+ struct btrfs_key key;
+ u16 item_size;
+ u64 num_blocks;
+ u64 new_blocks;
+ u64 device_id;
+ int ret;
+
+printk("adding disk %s\n", name);
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ num_blocks = btrfs_super_total_blocks(root->fs_info->disk_super);
+ bdev = open_bdev_excl(name, O_RDWR, sb);
+ if (IS_ERR(bdev)) {
+ ret = PTR_ERR(bdev);
+printk("open bdev excl failed ret %d\n", ret);
+ goto out_nolock;
+ }
+ set_blocksize(bdev, sb->s_blocksize);
+ new_blocks = bdev->bd_inode->i_size >> sb->s_blocksize_bits;
+ key.objectid = num_blocks;
+ key.offset = new_blocks;
+ key.flags = 0;
+ btrfs_set_key_type(&key, BTRFS_DEV_ITEM_KEY);
+
+ mutex_lock(&dev_root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(dev_root, 1);
+ item_size = sizeof(*dev_item) + namelen;
+printk("insert empty on %Lu %Lu %u size %d\n", num_blocks, new_blocks, key.flags, item_size);
+ ret = btrfs_insert_empty_item(trans, dev_root, path, &key, item_size);
+ if (ret) {
+printk("insert failed %d\n", ret);
+ close_bdev_excl(bdev);
+ if (ret > 0)
+ ret = -EEXIST;
+ goto out;
+ }
+ dev_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+ path->slots[0], struct btrfs_device_item);
+ btrfs_set_device_pathlen(dev_item, namelen);
+ memcpy(dev_item + 1, name, namelen);
+
+ device_id = btrfs_super_last_device_id(root->fs_info->disk_super) + 1;
+ btrfs_set_super_last_device_id(root->fs_info->disk_super, device_id);
+ btrfs_set_device_id(dev_item, device_id);
+ mark_buffer_dirty(path->nodes[0]);
+
+ ret = btrfs_insert_dev_radix(root, bdev, device_id, num_blocks,
+ new_blocks);
+
+ if (!ret) {
+ btrfs_set_super_total_blocks(root->fs_info->disk_super,
+ num_blocks + new_blocks);
+ i_size_write(root->fs_info->btree_inode,
+ (num_blocks + new_blocks) <<
+ root->fs_info->btree_inode->i_blkbits);
+ }
+
+out:
+ ret = btrfs_commit_transaction(trans, dev_root);
+ BUG_ON(ret);
+ mutex_unlock(&root->fs_info->fs_mutex);
+out_nolock:
+ btrfs_free_path(path);
+ btrfs_btree_balance_dirty(root);
+
+ return ret;
+}
+
+static int btrfs_ioctl(struct inode *inode, struct file *filp, unsigned int
+ cmd, unsigned long arg)
+{
+ struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_ioctl_vol_args vol_args;
+ int ret = 0;
+ struct btrfs_dir_item *di;
+ int namelen;
+ struct btrfs_path *path;
+ u64 root_dirid;
+
+ switch (cmd) {
+ case BTRFS_IOC_SNAP_CREATE:
+ if (copy_from_user(&vol_args,
+ (struct btrfs_ioctl_vol_args __user *)arg,
+ sizeof(vol_args)))
+ return -EFAULT;
+ namelen = strlen(vol_args.name);
+ if (namelen > BTRFS_VOL_NAME_MAX)
+ return -EINVAL;
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
+ mutex_lock(&root->fs_info->fs_mutex);
+ di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
+ path, root_dirid,
+ vol_args.name, namelen, 0);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ btrfs_free_path(path);
+ if (di && !IS_ERR(di))
+ return -EEXIST;
+
+ if (root == root->fs_info->tree_root)
+ ret = create_subvol(root, vol_args.name, namelen);
+ else
+ ret = create_snapshot(root, vol_args.name, namelen);
+ WARN_ON(ret);
+ break;
+ case BTRFS_IOC_ADD_DISK:
+ if (copy_from_user(&vol_args,
+ (struct btrfs_ioctl_vol_args __user *)arg,
+ sizeof(vol_args)))
+ return -EFAULT;
+ namelen = strlen(vol_args.name);
+ if (namelen > BTRFS_VOL_NAME_MAX)
+ return -EINVAL;
+ vol_args.name[namelen] = '\0';
+ ret = add_disk(root, vol_args.name, namelen);
+ break;
+ default:
+ return -ENOTTY;
+ }
+ return ret;
+}
+
+static struct kmem_cache *btrfs_inode_cachep;
+struct kmem_cache *btrfs_trans_handle_cachep;
+struct kmem_cache *btrfs_transaction_cachep;
+struct kmem_cache *btrfs_bit_radix_cachep;
+struct kmem_cache *btrfs_path_cachep;
+
+/*
+ * Called inside transaction, so use GFP_NOFS
+ */
+static struct inode *btrfs_alloc_inode(struct super_block *sb)
+{
+ struct btrfs_inode *ei;
+
+ ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
+ if (!ei)
+ return NULL;
+ return &ei->vfs_inode;
+}
+
+static void btrfs_destroy_inode(struct inode *inode)
+{
+ WARN_ON(!list_empty(&inode->i_dentry));
+ WARN_ON(inode->i_data.nrpages);
+
+ kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
+}
+
+static void init_once(void * foo, struct kmem_cache * cachep,
+ unsigned long flags)
+{
+ struct btrfs_inode *ei = (struct btrfs_inode *) foo;
+
+ if ((flags & (SLAB_CTOR_CONSTRUCTOR)) ==
+ SLAB_CTOR_CONSTRUCTOR) {
+ inode_init_once(&ei->vfs_inode);
+ }
+}
+
+static int init_inodecache(void)
+{
+ btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
+ sizeof(struct btrfs_inode),
+ 0, (SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD),
+ init_once, NULL);
+ btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
+ sizeof(struct btrfs_trans_handle),
+ 0, (SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD),
+ NULL, NULL);
+ btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
+ sizeof(struct btrfs_transaction),
+ 0, (SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD),
+ NULL, NULL);
+ btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
+ sizeof(struct btrfs_transaction),
+ 0, (SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD),
+ NULL, NULL);
+ btrfs_bit_radix_cachep = kmem_cache_create("btrfs_radix",
+ 256,
+ 0, (SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD |
+ SLAB_DESTROY_BY_RCU),
+ NULL, NULL);
+ if (btrfs_inode_cachep == NULL || btrfs_trans_handle_cachep == NULL ||
+ btrfs_transaction_cachep == NULL || btrfs_bit_radix_cachep == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
+static void destroy_inodecache(void)
+{
+ kmem_cache_destroy(btrfs_inode_cachep);
+ kmem_cache_destroy(btrfs_trans_handle_cachep);
+ kmem_cache_destroy(btrfs_transaction_cachep);
+ kmem_cache_destroy(btrfs_bit_radix_cachep);
+ kmem_cache_destroy(btrfs_path_cachep);
+}
+
+static int btrfs_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data, struct vfsmount *mnt)
+{
+ return get_sb_bdev(fs_type, flags, dev_name, data,
+ btrfs_fill_super, mnt);
+}
+
+static int btrfs_getattr(struct vfsmount *mnt,
+ struct dentry *dentry, struct kstat *stat)
+{
+ struct inode *inode = dentry->d_inode;
+ generic_fillattr(inode, stat);
+ stat->blksize = 256 * 1024;
+ return 0;
+}
+
+static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct btrfs_root *root = btrfs_sb(dentry->d_sb);
+ struct btrfs_super_block *disk_super = root->fs_info->disk_super;
+
+ buf->f_namelen = BTRFS_NAME_LEN;
+ buf->f_blocks = btrfs_super_total_blocks(disk_super);
+ buf->f_bfree = buf->f_blocks - btrfs_super_blocks_used(disk_super);
+ buf->f_bavail = buf->f_bfree;
+ buf->f_bsize = dentry->d_sb->s_blocksize;
+ buf->f_type = BTRFS_SUPER_MAGIC;
+ return 0;
+}
+
+static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
+ struct inode * new_dir,struct dentry *new_dentry)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *root = BTRFS_I(old_dir)->root;
+ struct inode *new_inode = new_dentry->d_inode;
+ struct inode *old_inode = old_dentry->d_inode;
+ struct timespec ctime = CURRENT_TIME;
+ struct btrfs_path *path;
+ struct btrfs_dir_item *di;
+ int ret;
+
+ if (S_ISDIR(old_inode->i_mode) && new_inode &&
+ new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
+ return -ENOTEMPTY;
+ }
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, new_dir);
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out_fail;
+ }
+
+ old_dentry->d_inode->i_nlink++;
+ old_dir->i_ctime = old_dir->i_mtime = ctime;
+ new_dir->i_ctime = new_dir->i_mtime = ctime;
+ old_inode->i_ctime = ctime;
+ if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
+ struct btrfs_key *location = &BTRFS_I(new_dir)->location;
+ u64 old_parent_oid;
+ di = btrfs_lookup_dir_item(trans, root, path, old_inode->i_ino,
+ "..", 2, -1);
+ if (IS_ERR(di)) {
+ ret = PTR_ERR(di);
+ goto out_fail;
+ }
+ if (!di) {
+ ret = -ENOENT;
+ goto out_fail;
+ }
+ old_parent_oid = btrfs_disk_key_objectid(&di->location);
+ ret = btrfs_del_item(trans, root, path);
+ if (ret) {
+ ret = -EIO;
+ goto out_fail;
+ }
+ btrfs_release_path(root, path);
+
+ di = btrfs_lookup_dir_index_item(trans, root, path,
+ old_inode->i_ino,
+ old_parent_oid,
+ "..", 2, -1);
+ if (IS_ERR(di)) {
+ ret = PTR_ERR(di);
+ goto out_fail;
+ }
+ if (!di) {
+ ret = -ENOENT;
+ goto out_fail;
+ }
+ ret = btrfs_del_item(trans, root, path);
+ if (ret) {
+ ret = -EIO;
+ goto out_fail;
+ }
+ btrfs_release_path(root, path);
+
+ ret = btrfs_insert_dir_item(trans, root, "..", 2,
+ old_inode->i_ino, location,
+ BTRFS_FT_DIR);
+ if (ret)
+ goto out_fail;
+ }
+
+
+ ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
+ if (ret)
+ goto out_fail;
+
+ if (new_inode) {
+ new_inode->i_ctime = CURRENT_TIME;
+ ret = btrfs_unlink_trans(trans, root, new_dir, new_dentry);
+ if (ret)
+ goto out_fail;
+ if (S_ISDIR(new_inode->i_mode))
+ clear_nlink(new_inode);
+ else
+ drop_nlink(new_inode);
+ btrfs_update_inode(trans, root, new_inode);
+ }
+ ret = btrfs_add_link(trans, new_dentry, old_inode);
+ if (ret)
+ goto out_fail;
+
+out_fail:
+ btrfs_free_path(path);
+ btrfs_end_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ return ret;
+}
+
+static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
+ const char *symname)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *root = BTRFS_I(dir)->root;
+ struct btrfs_path *path;
+ struct btrfs_key key;
+ struct inode *inode;
+ int err;
+ int drop_inode = 0;
+ u64 objectid;
+ int name_len;
+ int datasize;
+ char *ptr;
+ struct btrfs_file_extent_item *ei;
+
+ name_len = strlen(symname) + 1;
+ if (name_len > BTRFS_MAX_INLINE_DATA_SIZE(root))
+ return -ENAMETOOLONG;
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, dir);
+
+ err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
+ if (err) {
+ err = -ENOSPC;
+ goto out_unlock;
+ }
+
+ inode = btrfs_new_inode(trans, root, objectid,
+ BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
+ err = PTR_ERR(inode);
+ if (IS_ERR(inode))
+ goto out_unlock;
+
+ btrfs_set_trans_block_group(trans, inode);
+ err = btrfs_add_nondir(trans, dentry, inode);
+ if (err)
+ drop_inode = 1;
+ else {
+ inode->i_mapping->a_ops = &btrfs_aops;
+ inode->i_fop = &btrfs_file_operations;
+ inode->i_op = &btrfs_file_inode_operations;
+ }
+ dir->i_sb->s_dirt = 1;
+ btrfs_update_inode_block_group(trans, inode);
+ btrfs_update_inode_block_group(trans, dir);
+ if (drop_inode)
+ goto out_unlock;
+
+ path = btrfs_alloc_path();
+ BUG_ON(!path);
+ key.objectid = inode->i_ino;
+ key.offset = 0;
+ key.flags = 0;
+ btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
+ datasize = btrfs_file_extent_calc_inline_size(name_len);
+ err = btrfs_insert_empty_item(trans, root, path, &key,
+ datasize);
+ BUG_ON(err);
+ ei = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+ path->slots[0], struct btrfs_file_extent_item);
+ btrfs_set_file_extent_generation(ei, trans->transid);
+ btrfs_set_file_extent_type(ei,
+ BTRFS_FILE_EXTENT_INLINE);
+ ptr = btrfs_file_extent_inline_start(ei);
+ btrfs_memcpy(root, path->nodes[0]->b_data,
+ ptr, symname, name_len);
+ mark_buffer_dirty(path->nodes[0]);
+ btrfs_free_path(path);
+ inode->i_op = &btrfs_symlink_inode_operations;
+ inode->i_mapping->a_ops = &btrfs_symlink_aops;
+ inode->i_size = name_len - 1;
+ btrfs_update_inode(trans, root, inode);
+ err = 0;
+
+out_unlock:
+ btrfs_end_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+
+ if (drop_inode) {
+ inode_dec_link_count(inode);
+ iput(inode);
+ }
+ btrfs_btree_balance_dirty(root);
+ return err;
+}
+
+static struct file_system_type btrfs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "btrfs",
+ .get_sb = btrfs_get_sb,
+ .kill_sb = kill_block_super,
+ .fs_flags = FS_REQUIRES_DEV,
+};
+
+static struct super_operations btrfs_super_ops = {
+ .delete_inode = btrfs_delete_inode,
+ .put_super = btrfs_put_super,
+ .read_inode = btrfs_read_locked_inode,
+ .write_super = btrfs_write_super,
+ .sync_fs = btrfs_sync_fs,
+ .write_inode = btrfs_write_inode,
+ .dirty_inode = btrfs_dirty_inode,
+ .alloc_inode = btrfs_alloc_inode,
+ .destroy_inode = btrfs_destroy_inode,
+ .statfs = btrfs_statfs,
+};
+
+static struct inode_operations btrfs_dir_inode_operations = {
+ .lookup = btrfs_lookup,
+ .create = btrfs_create,
+ .unlink = btrfs_unlink,
+ .link = btrfs_link,
+ .mkdir = btrfs_mkdir,
+ .rmdir = btrfs_rmdir,
+ .rename = btrfs_rename,
+ .symlink = btrfs_symlink,
+ .setattr = btrfs_setattr,
+};
+
+static struct inode_operations btrfs_dir_ro_inode_operations = {
+ .lookup = btrfs_lookup,
+};
+
+static struct file_operations btrfs_dir_file_operations = {
+ .llseek = generic_file_llseek,
+ .read = generic_read_dir,
+ .readdir = btrfs_readdir,
+ .ioctl = btrfs_ioctl,
+};
+
+static struct address_space_operations btrfs_aops = {
+ .readpage = btrfs_readpage,
+ .writepage = btrfs_writepage,
+ .sync_page = block_sync_page,
+ .prepare_write = btrfs_prepare_write,
+ .commit_write = btrfs_commit_write,
+ .bmap = btrfs_bmap,
+};
+
+static struct address_space_operations btrfs_symlink_aops = {
+ .readpage = btrfs_readpage,
+ .writepage = btrfs_writepage,
+};
+
+static struct inode_operations btrfs_file_inode_operations = {
+ .truncate = btrfs_truncate,
+ .getattr = btrfs_getattr,
+ .setattr = btrfs_setattr,
+};
+
+static struct file_operations btrfs_file_operations = {
+ .llseek = generic_file_llseek,
+ .read = do_sync_read,
+ .aio_read = btrfs_file_aio_read,
+ .write = btrfs_file_write,
+ .mmap = generic_file_mmap,
+ .open = generic_file_open,
+ .ioctl = btrfs_ioctl,
+ .fsync = btrfs_sync_file,
+};
+
+static struct inode_operations btrfs_symlink_inode_operations = {
+ .readlink = generic_readlink,
+ .follow_link = page_follow_link_light,
+ .put_link = page_put_link,
+};
+
+static int __init init_btrfs_fs(void)
+{
+ int err;
+ printk("btrfs loaded!\n");
+ err = init_inodecache();
+ if (err)
+ return err;
return register_filesystem(&btrfs_fs_type);
+ destroy_inodecache();
+ return err;
}
static void __exit exit_btrfs_fs(void)
{
+ destroy_inodecache();
unregister_filesystem(&btrfs_fs_type);
printk("btrfs unloaded\n");
}
projects / linux-2.6-block.git / blobdiff