2575 lines
67 KiB
C
2575 lines
67 KiB
C
/*
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* Copyright (C) 2007 Oracle. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License v2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public
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* License along with this program; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 021110-1307, USA.
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*/
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#include <linux/buffer_head.h>
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#include <linux/fs.h>
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#include <linux/pagemap.h>
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#include <linux/highmem.h>
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#include <linux/time.h>
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#include <linux/init.h>
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#include <linux/string.h>
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#include <linux/smp_lock.h>
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#include <linux/backing-dev.h>
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#include <linux/mpage.h>
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#include <linux/swap.h>
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#include <linux/writeback.h>
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#include <linux/statfs.h>
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#include <linux/compat.h>
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#include <linux/bit_spinlock.h>
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#include <linux/version.h>
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#include "ctree.h"
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#include "disk-io.h"
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#include "transaction.h"
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#include "btrfs_inode.h"
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#include "ioctl.h"
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#include "print-tree.h"
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struct btrfs_iget_args {
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u64 ino;
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struct btrfs_root *root;
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};
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static struct inode_operations btrfs_dir_inode_operations;
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static struct inode_operations btrfs_symlink_inode_operations;
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static struct inode_operations btrfs_dir_ro_inode_operations;
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static struct inode_operations btrfs_special_inode_operations;
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static struct inode_operations btrfs_file_inode_operations;
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static struct address_space_operations btrfs_aops;
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static struct address_space_operations btrfs_symlink_aops;
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static struct file_operations btrfs_dir_file_operations;
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static struct kmem_cache *btrfs_inode_cachep;
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struct kmem_cache *btrfs_trans_handle_cachep;
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struct kmem_cache *btrfs_transaction_cachep;
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struct kmem_cache *btrfs_bit_radix_cachep;
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struct kmem_cache *btrfs_path_cachep;
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#define S_SHIFT 12
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static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = {
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[S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE,
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[S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR,
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[S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV,
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[S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV,
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[S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO,
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[S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK,
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[S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK,
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};
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void btrfs_read_locked_inode(struct inode *inode)
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{
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struct btrfs_path *path;
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struct btrfs_inode_item *inode_item;
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struct btrfs_root *root = BTRFS_I(inode)->root;
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struct btrfs_key location;
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u64 alloc_group_block;
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u32 rdev;
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int ret;
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path = btrfs_alloc_path();
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BUG_ON(!path);
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mutex_lock(&root->fs_info->fs_mutex);
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memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
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ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
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if (ret) {
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btrfs_free_path(path);
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goto make_bad;
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}
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inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
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path->slots[0],
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struct btrfs_inode_item);
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inode->i_mode = btrfs_inode_mode(inode_item);
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inode->i_nlink = btrfs_inode_nlink(inode_item);
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inode->i_uid = btrfs_inode_uid(inode_item);
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inode->i_gid = btrfs_inode_gid(inode_item);
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inode->i_size = btrfs_inode_size(inode_item);
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inode->i_atime.tv_sec = btrfs_timespec_sec(&inode_item->atime);
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inode->i_atime.tv_nsec = btrfs_timespec_nsec(&inode_item->atime);
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inode->i_mtime.tv_sec = btrfs_timespec_sec(&inode_item->mtime);
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inode->i_mtime.tv_nsec = btrfs_timespec_nsec(&inode_item->mtime);
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inode->i_ctime.tv_sec = btrfs_timespec_sec(&inode_item->ctime);
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inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
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inode->i_blocks = btrfs_inode_nblocks(inode_item);
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inode->i_generation = btrfs_inode_generation(inode_item);
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inode->i_rdev = 0;
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rdev = btrfs_inode_rdev(inode_item);
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alloc_group_block = btrfs_inode_block_group(inode_item);
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BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
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alloc_group_block);
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btrfs_free_path(path);
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inode_item = NULL;
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mutex_unlock(&root->fs_info->fs_mutex);
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switch (inode->i_mode & S_IFMT) {
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case S_IFREG:
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inode->i_mapping->a_ops = &btrfs_aops;
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inode->i_fop = &btrfs_file_operations;
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inode->i_op = &btrfs_file_inode_operations;
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break;
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case S_IFDIR:
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inode->i_fop = &btrfs_dir_file_operations;
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if (root == root->fs_info->tree_root)
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inode->i_op = &btrfs_dir_ro_inode_operations;
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else
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inode->i_op = &btrfs_dir_inode_operations;
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break;
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case S_IFLNK:
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inode->i_op = &btrfs_symlink_inode_operations;
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inode->i_mapping->a_ops = &btrfs_symlink_aops;
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break;
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default:
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init_special_inode(inode, inode->i_mode, rdev);
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break;
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}
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return;
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make_bad:
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btrfs_release_path(root, path);
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btrfs_free_path(path);
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mutex_unlock(&root->fs_info->fs_mutex);
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make_bad_inode(inode);
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}
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static void fill_inode_item(struct btrfs_inode_item *item,
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struct inode *inode)
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{
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btrfs_set_inode_uid(item, inode->i_uid);
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btrfs_set_inode_gid(item, inode->i_gid);
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btrfs_set_inode_size(item, inode->i_size);
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btrfs_set_inode_mode(item, inode->i_mode);
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btrfs_set_inode_nlink(item, inode->i_nlink);
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btrfs_set_timespec_sec(&item->atime, inode->i_atime.tv_sec);
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btrfs_set_timespec_nsec(&item->atime, inode->i_atime.tv_nsec);
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btrfs_set_timespec_sec(&item->mtime, inode->i_mtime.tv_sec);
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btrfs_set_timespec_nsec(&item->mtime, inode->i_mtime.tv_nsec);
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btrfs_set_timespec_sec(&item->ctime, inode->i_ctime.tv_sec);
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btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
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btrfs_set_inode_nblocks(item, inode->i_blocks);
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btrfs_set_inode_generation(item, inode->i_generation);
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btrfs_set_inode_rdev(item, inode->i_rdev);
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btrfs_set_inode_block_group(item,
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BTRFS_I(inode)->block_group->key.objectid);
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}
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static int btrfs_update_inode(struct btrfs_trans_handle *trans,
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struct btrfs_root *root,
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struct inode *inode)
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{
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struct btrfs_inode_item *inode_item;
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struct btrfs_path *path;
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int ret;
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path = btrfs_alloc_path();
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BUG_ON(!path);
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ret = btrfs_lookup_inode(trans, root, path,
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&BTRFS_I(inode)->location, 1);
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if (ret) {
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if (ret > 0)
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ret = -ENOENT;
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goto failed;
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}
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inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
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path->slots[0],
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struct btrfs_inode_item);
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fill_inode_item(inode_item, inode);
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btrfs_mark_buffer_dirty(path->nodes[0]);
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ret = 0;
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failed:
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btrfs_release_path(root, path);
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btrfs_free_path(path);
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return ret;
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}
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static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
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struct btrfs_root *root,
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struct inode *dir,
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struct dentry *dentry)
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{
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struct btrfs_path *path;
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const char *name = dentry->d_name.name;
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int name_len = dentry->d_name.len;
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int ret = 0;
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u64 objectid;
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struct btrfs_dir_item *di;
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path = btrfs_alloc_path();
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if (!path) {
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ret = -ENOMEM;
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goto err;
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}
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di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
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name, name_len, -1);
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if (IS_ERR(di)) {
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ret = PTR_ERR(di);
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goto err;
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}
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if (!di) {
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ret = -ENOENT;
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goto err;
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}
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objectid = btrfs_disk_key_objectid(&di->location);
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ret = btrfs_delete_one_dir_name(trans, root, path, di);
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if (ret)
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goto err;
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btrfs_release_path(root, path);
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di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
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objectid, name, name_len, -1);
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if (IS_ERR(di)) {
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ret = PTR_ERR(di);
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goto err;
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}
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if (!di) {
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ret = -ENOENT;
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goto err;
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}
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ret = btrfs_delete_one_dir_name(trans, root, path, di);
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dentry->d_inode->i_ctime = dir->i_ctime;
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err:
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btrfs_free_path(path);
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if (!ret) {
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dir->i_size -= name_len * 2;
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dir->i_mtime = dir->i_ctime = CURRENT_TIME;
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btrfs_update_inode(trans, root, dir);
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drop_nlink(dentry->d_inode);
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ret = btrfs_update_inode(trans, root, dentry->d_inode);
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dir->i_sb->s_dirt = 1;
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}
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return ret;
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}
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static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
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{
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struct btrfs_root *root;
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struct btrfs_trans_handle *trans;
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int ret;
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root = BTRFS_I(dir)->root;
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mutex_lock(&root->fs_info->fs_mutex);
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trans = btrfs_start_transaction(root, 1);
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btrfs_set_trans_block_group(trans, dir);
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ret = btrfs_unlink_trans(trans, root, dir, dentry);
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btrfs_end_transaction(trans, root);
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mutex_unlock(&root->fs_info->fs_mutex);
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btrfs_btree_balance_dirty(root);
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return ret;
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}
|
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|
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static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
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{
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struct inode *inode = dentry->d_inode;
|
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int err;
|
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int ret;
|
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struct btrfs_root *root = BTRFS_I(dir)->root;
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struct btrfs_path *path;
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struct btrfs_key key;
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struct btrfs_trans_handle *trans;
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struct btrfs_key found_key;
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int found_type;
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struct btrfs_leaf *leaf;
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char *goodnames = "..";
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path = btrfs_alloc_path();
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BUG_ON(!path);
|
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mutex_lock(&root->fs_info->fs_mutex);
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trans = btrfs_start_transaction(root, 1);
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btrfs_set_trans_block_group(trans, dir);
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key.objectid = inode->i_ino;
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key.offset = (u64)-1;
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key.flags = (u32)-1;
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while(1) {
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ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
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if (ret < 0) {
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err = ret;
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goto out;
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}
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BUG_ON(ret == 0);
|
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if (path->slots[0] == 0) {
|
|
err = -ENOENT;
|
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goto out;
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}
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path->slots[0]--;
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leaf = btrfs_buffer_leaf(path->nodes[0]);
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btrfs_disk_key_to_cpu(&found_key,
|
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&leaf->items[path->slots[0]].key);
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found_type = btrfs_key_type(&found_key);
|
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if (found_key.objectid != inode->i_ino) {
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err = -ENOENT;
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goto out;
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}
|
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if ((found_type != BTRFS_DIR_ITEM_KEY &&
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found_type != BTRFS_DIR_INDEX_KEY) ||
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(!btrfs_match_dir_item_name(root, path, goodnames, 2) &&
|
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!btrfs_match_dir_item_name(root, path, goodnames, 1))) {
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err = -ENOTEMPTY;
|
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goto out;
|
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}
|
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ret = btrfs_del_item(trans, root, path);
|
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BUG_ON(ret);
|
|
|
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if (found_type == BTRFS_DIR_ITEM_KEY && found_key.offset == 1)
|
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break;
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btrfs_release_path(root, path);
|
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}
|
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ret = 0;
|
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btrfs_release_path(root, path);
|
|
|
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/* now the directory is empty */
|
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err = btrfs_unlink_trans(trans, root, dir, dentry);
|
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if (!err) {
|
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inode->i_size = 0;
|
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}
|
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out:
|
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btrfs_release_path(root, path);
|
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btrfs_free_path(path);
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
ret = btrfs_end_transaction(trans, root);
|
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btrfs_btree_balance_dirty(root);
|
|
if (ret && !err)
|
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err = ret;
|
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return err;
|
|
}
|
|
|
|
static int btrfs_free_inode(struct btrfs_trans_handle *trans,
|
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struct btrfs_root *root,
|
|
struct inode *inode)
|
|
{
|
|
struct btrfs_path *path;
|
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int ret;
|
|
|
|
clear_inode(inode);
|
|
|
|
path = btrfs_alloc_path();
|
|
BUG_ON(!path);
|
|
ret = btrfs_lookup_inode(trans, root, path,
|
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&BTRFS_I(inode)->location, -1);
|
|
if (ret > 0)
|
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ret = -ENOENT;
|
|
if (!ret)
|
|
ret = btrfs_del_item(trans, root, path);
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* this can truncate away extent items, csum items and directory items.
|
|
* It starts at a high offset and removes keys until it can't find
|
|
* any higher than i_size.
|
|
*
|
|
* csum items that cross the new i_size are truncated to the new size
|
|
* as well.
|
|
*/
|
|
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();
|
|
path->reada = -1;
|
|
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]--;
|
|
}
|
|
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;
|
|
|
|
/* FIXME, shrink the extent if the ref count is only 1 */
|
|
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;
|
|
btrfs_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);
|
|
if (ret)
|
|
goto error;
|
|
} 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;
|
|
}
|
|
|
|
/*
|
|
* taken from block_truncate_page, but does cow as it zeros out
|
|
* any bytes left in the last page in the file.
|
|
*/
|
|
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 = 0;
|
|
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 = btrfs_readpage(NULL, page);
|
|
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 = btrfs_drop_extents(trans, root, inode,
|
|
page->index << PAGE_CACHE_SHIFT,
|
|
(page->index + 1) << PAGE_CACHE_SHIFT,
|
|
&alloc_hint);
|
|
if (ret)
|
|
goto out;
|
|
ret = btrfs_alloc_extent(trans, root, inode->i_ino, 1, 0,
|
|
alloc_hint, (u64)-1, &ins, 1);
|
|
if (ret)
|
|
goto out;
|
|
ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
|
|
page->index << PAGE_CACHE_SHIFT,
|
|
ins.objectid, 1, 1);
|
|
if (ret)
|
|
goto out;
|
|
SetPageChecked(page);
|
|
kaddr = kmap(page);
|
|
memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
|
|
flush_dcache_page(page);
|
|
ret = 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);
|
|
btrfs_end_transaction(trans, root);
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
if (err)
|
|
return err;
|
|
}
|
|
out:
|
|
err = inode_setattr(inode, attr);
|
|
|
|
return err;
|
|
}
|
|
void btrfs_delete_inode(struct inode *inode)
|
|
{
|
|
struct btrfs_trans_handle *trans;
|
|
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;
|
|
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);
|
|
if (ret)
|
|
goto no_delete_lock;
|
|
ret = btrfs_free_inode(trans, root, inode);
|
|
if (ret)
|
|
goto no_delete_lock;
|
|
btrfs_end_transaction(trans, root);
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
btrfs_btree_balance_dirty(root);
|
|
return;
|
|
|
|
no_delete_lock:
|
|
btrfs_end_transaction(trans, root);
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
btrfs_btree_balance_dirty(root);
|
|
no_delete:
|
|
clear_inode(inode);
|
|
}
|
|
|
|
/*
|
|
* this returns the key found in the dir entry in the location pointer.
|
|
* If no dir entries were found, location->objectid is 0.
|
|
*/
|
|
static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
|
|
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_I(dir)->root;
|
|
int ret;
|
|
|
|
path = btrfs_alloc_path();
|
|
BUG_ON(!path);
|
|
di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
|
|
namelen, 0);
|
|
if (!di || IS_ERR(di)) {
|
|
location->objectid = 0;
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
btrfs_disk_key_to_cpu(location, &di->location);
|
|
out:
|
|
btrfs_release_path(root, path);
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* when we hit a tree root in a directory, the btrfs part of the inode
|
|
* needs to be changed to reflect the root directory of the tree root. This
|
|
* is kind of like crossing a mount point.
|
|
*/
|
|
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);
|
|
}
|
|
|
|
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;
|
|
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);
|
|
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 (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) {
|
|
/* the inode and parent dir are two different roots */
|
|
if (sub_root != 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 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_I(inode)->root;
|
|
struct btrfs_item *item;
|
|
struct btrfs_dir_item *di;
|
|
struct btrfs_key key;
|
|
struct btrfs_path *path;
|
|
int ret;
|
|
u32 nritems;
|
|
struct btrfs_leaf *leaf;
|
|
int slot;
|
|
int advance;
|
|
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, key_type);
|
|
key.offset = filp->f_pos;
|
|
path = btrfs_alloc_path();
|
|
path->reada = 1;
|
|
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
|
|
if (ret < 0)
|
|
goto err;
|
|
advance = 0;
|
|
while(1) {
|
|
leaf = btrfs_buffer_leaf(path->nodes[0]);
|
|
nritems = btrfs_header_nritems(&leaf->header);
|
|
slot = path->slots[0];
|
|
if (advance || slot >= nritems) {
|
|
if (slot >= nritems -1) {
|
|
ret = btrfs_next_leaf(root, path);
|
|
if (ret)
|
|
break;
|
|
leaf = btrfs_buffer_leaf(path->nodes[0]);
|
|
nritems = btrfs_header_nritems(&leaf->header);
|
|
slot = path->slots[0];
|
|
} else {
|
|
slot++;
|
|
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) != 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);
|
|
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++;
|
|
nopos:
|
|
ret = 0;
|
|
err:
|
|
btrfs_release_path(root, path);
|
|
btrfs_free_path(path);
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
return ret;
|
|
}
|
|
|
|
int btrfs_write_inode(struct inode *inode, int wait)
|
|
{
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* This is somewhat expensive, updating the tree every time the
|
|
* inode changes. But, it is most likely to find the inode in cache.
|
|
* FIXME, needs more benchmarking...there are no reasons other than performance
|
|
* to keep or drop this code.
|
|
*/
|
|
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);
|
|
}
|
|
|
|
static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
|
|
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_key *location;
|
|
int ret;
|
|
int owner;
|
|
|
|
inode = new_inode(root->fs_info->sb);
|
|
if (!inode)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
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;
|
|
fill_inode_item(&inode_item, inode);
|
|
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);
|
|
if (ret)
|
|
return ERR_PTR(ret);
|
|
insert_inode_hash(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;
|
|
struct btrfs_key key;
|
|
struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
|
|
struct inode *parent_inode;
|
|
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,
|
|
&key, btrfs_inode_type(inode));
|
|
if (ret == 0) {
|
|
parent_inode = dentry->d_parent->d_inode;
|
|
parent_inode->i_size += dentry->d_name.len * 2;
|
|
parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
|
|
ret = btrfs_update_inode(trans, root,
|
|
dentry->d_parent->d_inode);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
|
|
struct dentry *dentry, struct inode *inode)
|
|
{
|
|
int err = btrfs_add_link(trans, dentry, inode);
|
|
if (!err) {
|
|
d_instantiate(dentry, inode);
|
|
return 0;
|
|
}
|
|
if (err > 0)
|
|
err = -EEXIST;
|
|
return err;
|
|
}
|
|
|
|
static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
|
|
int mode, dev_t rdev)
|
|
{
|
|
struct btrfs_trans_handle *trans;
|
|
struct btrfs_root *root = BTRFS_I(dir)->root;
|
|
struct inode *inode;
|
|
int err;
|
|
int drop_inode = 0;
|
|
u64 objectid;
|
|
|
|
if (!new_valid_dev(rdev))
|
|
return -EINVAL;
|
|
|
|
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, mode);
|
|
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_op = &btrfs_special_inode_operations;
|
|
init_special_inode(inode, inode->i_mode, rdev);
|
|
}
|
|
dir->i_sb->s_dirt = 1;
|
|
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_create(struct inode *dir, struct dentry *dentry,
|
|
int mode, struct nameidata *nd)
|
|
{
|
|
struct btrfs_trans_handle *trans;
|
|
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);
|
|
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;
|
|
|
|
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);
|
|
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);
|
|
err = btrfs_update_inode(trans, root, inode);
|
|
if (err)
|
|
drop_inode = 1;
|
|
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* FIBMAP and others want to pass in a fake buffer head. They need to
|
|
* use BTRFS_GET_BLOCK_NO_DIRECT to make sure we don't try to memcpy
|
|
* any packed file data into the fake bh
|
|
*/
|
|
#define BTRFS_GET_BLOCK_NO_CREATE 0
|
|
#define BTRFS_GET_BLOCK_CREATE 1
|
|
#define BTRFS_GET_BLOCK_NO_DIRECT 2
|
|
|
|
/*
|
|
* FIXME create==1 doe not work.
|
|
*/
|
|
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);
|
|
if (create & BTRFS_GET_BLOCK_CREATE) {
|
|
/*
|
|
* danger!, this only works if the page is properly up
|
|
* to date somehow
|
|
*/
|
|
trans = btrfs_start_transaction(root, 1);
|
|
if (!trans) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
ret = btrfs_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,
|
|
objectid,
|
|
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, 0, alloc_hint, (u64)-1,
|
|
&ins, 1);
|
|
if (ret) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
|
|
iblock << inode->i_blkbits,
|
|
ins.objectid, ins.offset,
|
|
ins.offset);
|
|
if (ret) {
|
|
err = ret;
|
|
goto out;
|
|
}
|
|
btrfs_map_bh_to_logical(root, result, ins.objectid);
|
|
}
|
|
out:
|
|
if (trans) {
|
|
ret = btrfs_end_transaction(trans, root);
|
|
if (!err)
|
|
err = ret;
|
|
}
|
|
btrfs_free_path(path);
|
|
return err;
|
|
}
|
|
|
|
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_csum(struct inode *inode, sector_t iblock,
|
|
struct buffer_head *result, int create)
|
|
{
|
|
int ret;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct page *page = result->b_page;
|
|
u64 offset = (page->index << PAGE_CACHE_SHIFT) + bh_offset(result);
|
|
struct btrfs_csum_item *item;
|
|
struct btrfs_path *path = NULL;
|
|
|
|
mutex_lock(&root->fs_info->fs_mutex);
|
|
ret = btrfs_get_block_lock(inode, iblock, result, create);
|
|
if (ret)
|
|
goto out;
|
|
|
|
path = btrfs_alloc_path();
|
|
item = btrfs_lookup_csum(NULL, root, path, inode->i_ino, offset, 0);
|
|
if (IS_ERR(item)) {
|
|
ret = PTR_ERR(item);
|
|
/* a csum that isn't present is a preallocated region. */
|
|
if (ret == -ENOENT || ret == -EFBIG)
|
|
ret = 0;
|
|
result->b_private = NULL;
|
|
goto out;
|
|
}
|
|
memcpy((char *)&result->b_private, &item->csum, BTRFS_CRC32_SIZE);
|
|
out:
|
|
if (path)
|
|
btrfs_free_path(path);
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
return ret;
|
|
}
|
|
|
|
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 buffer_io_error(struct buffer_head *bh)
|
|
{
|
|
char b[BDEVNAME_SIZE];
|
|
|
|
printk(KERN_ERR "Buffer I/O error on device %s, logical block %Lu\n",
|
|
bdevname(bh->b_bdev, b),
|
|
(unsigned long long)bh->b_blocknr);
|
|
}
|
|
|
|
/*
|
|
* I/O completion handler for block_read_full_page() - pages
|
|
* which come unlocked at the end of I/O.
|
|
*/
|
|
static void btrfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
|
|
{
|
|
unsigned long flags;
|
|
struct buffer_head *first;
|
|
struct buffer_head *tmp;
|
|
struct page *page;
|
|
int page_uptodate = 1;
|
|
struct inode *inode;
|
|
int ret;
|
|
|
|
BUG_ON(!buffer_async_read(bh));
|
|
|
|
page = bh->b_page;
|
|
inode = page->mapping->host;
|
|
if (uptodate) {
|
|
void *kaddr;
|
|
struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
|
|
if (bh->b_private) {
|
|
char csum[BTRFS_CRC32_SIZE];
|
|
kaddr = kmap_atomic(page, KM_IRQ0);
|
|
ret = btrfs_csum_data(root, kaddr + bh_offset(bh),
|
|
bh->b_size, csum);
|
|
BUG_ON(ret);
|
|
if (memcmp(csum, &bh->b_private, BTRFS_CRC32_SIZE)) {
|
|
u64 offset;
|
|
offset = (page->index << PAGE_CACHE_SHIFT) +
|
|
bh_offset(bh);
|
|
printk("btrfs csum failed ino %lu off %llu\n",
|
|
page->mapping->host->i_ino,
|
|
(unsigned long long)offset);
|
|
memset(kaddr + bh_offset(bh), 1, bh->b_size);
|
|
flush_dcache_page(page);
|
|
}
|
|
kunmap_atomic(kaddr, KM_IRQ0);
|
|
}
|
|
set_buffer_uptodate(bh);
|
|
} else {
|
|
clear_buffer_uptodate(bh);
|
|
if (printk_ratelimit())
|
|
buffer_io_error(bh);
|
|
SetPageError(page);
|
|
}
|
|
|
|
/*
|
|
* Be _very_ careful from here on. Bad things can happen if
|
|
* two buffer heads end IO at almost the same time and both
|
|
* decide that the page is now completely done.
|
|
*/
|
|
first = page_buffers(page);
|
|
local_irq_save(flags);
|
|
bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
|
|
clear_buffer_async_read(bh);
|
|
unlock_buffer(bh);
|
|
tmp = bh;
|
|
do {
|
|
if (!buffer_uptodate(tmp))
|
|
page_uptodate = 0;
|
|
if (buffer_async_read(tmp)) {
|
|
BUG_ON(!buffer_locked(tmp));
|
|
goto still_busy;
|
|
}
|
|
tmp = tmp->b_this_page;
|
|
} while (tmp != bh);
|
|
bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
|
|
local_irq_restore(flags);
|
|
|
|
/*
|
|
* If none of the buffers had errors and they are all
|
|
* uptodate then we can set the page uptodate.
|
|
*/
|
|
if (page_uptodate && !PageError(page))
|
|
SetPageUptodate(page);
|
|
unlock_page(page);
|
|
return;
|
|
|
|
still_busy:
|
|
bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
|
|
local_irq_restore(flags);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Generic "read page" function for block devices that have the normal
|
|
* get_block functionality. This is most of the block device filesystems.
|
|
* Reads the page asynchronously --- the unlock_buffer() and
|
|
* set/clear_buffer_uptodate() functions propagate buffer state into the
|
|
* page struct once IO has completed.
|
|
*/
|
|
int btrfs_readpage(struct file *file, struct page *page)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
sector_t iblock, lblock;
|
|
struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
|
|
unsigned int blocksize;
|
|
int nr, i;
|
|
int fully_mapped = 1;
|
|
|
|
BUG_ON(!PageLocked(page));
|
|
blocksize = 1 << inode->i_blkbits;
|
|
if (!page_has_buffers(page))
|
|
create_empty_buffers(page, blocksize, 0);
|
|
head = page_buffers(page);
|
|
|
|
iblock = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
|
|
lblock = (i_size_read(inode)+blocksize-1) >> inode->i_blkbits;
|
|
bh = head;
|
|
nr = 0;
|
|
i = 0;
|
|
|
|
do {
|
|
if (buffer_uptodate(bh))
|
|
continue;
|
|
|
|
if (!buffer_mapped(bh)) {
|
|
int err = 0;
|
|
|
|
fully_mapped = 0;
|
|
if (iblock < lblock) {
|
|
WARN_ON(bh->b_size != blocksize);
|
|
err = btrfs_get_block_csum(inode, iblock,
|
|
bh, 0);
|
|
if (err)
|
|
SetPageError(page);
|
|
}
|
|
if (!buffer_mapped(bh)) {
|
|
void *kaddr = kmap_atomic(page, KM_USER0);
|
|
memset(kaddr + i * blocksize, 0, blocksize);
|
|
flush_dcache_page(page);
|
|
kunmap_atomic(kaddr, KM_USER0);
|
|
if (!err)
|
|
set_buffer_uptodate(bh);
|
|
continue;
|
|
}
|
|
/*
|
|
* get_block() might have updated the buffer
|
|
* synchronously
|
|
*/
|
|
if (buffer_uptodate(bh))
|
|
continue;
|
|
}
|
|
arr[nr++] = bh;
|
|
} while (i++, iblock++, (bh = bh->b_this_page) != head);
|
|
|
|
if (fully_mapped)
|
|
SetPageMappedToDisk(page);
|
|
|
|
if (!nr) {
|
|
/*
|
|
* All buffers are uptodate - we can set the page uptodate
|
|
* as well. But not if get_block() returned an error.
|
|
*/
|
|
if (!PageError(page))
|
|
SetPageUptodate(page);
|
|
unlock_page(page);
|
|
return 0;
|
|
}
|
|
|
|
/* Stage two: lock the buffers */
|
|
for (i = 0; i < nr; i++) {
|
|
bh = arr[i];
|
|
lock_buffer(bh);
|
|
bh->b_end_io = btrfs_end_buffer_async_read;
|
|
set_buffer_async_read(bh);
|
|
}
|
|
|
|
/*
|
|
* Stage 3: start the IO. Check for uptodateness
|
|
* inside the buffer lock in case another process reading
|
|
* the underlying blockdev brought it uptodate (the sct fix).
|
|
*/
|
|
for (i = 0; i < nr; i++) {
|
|
bh = arr[i];
|
|
if (buffer_uptodate(bh))
|
|
btrfs_end_buffer_async_read(bh, 1);
|
|
else
|
|
submit_bh(READ, bh);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Aside from a tiny bit of packed file data handling, this is the
|
|
* same as the generic code.
|
|
*
|
|
* 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;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
|
|
BUG_ON(!PageLocked(page));
|
|
|
|
last_block = (i_size_read(inode) - 1) >> inode->i_blkbits;
|
|
|
|
/* no csumming allowed when from PF_MEMALLOC */
|
|
if (current->flags & PF_MEMALLOC) {
|
|
redirty_page_for_writepage(wbc, page);
|
|
unlock_page(page);
|
|
return 0;
|
|
}
|
|
|
|
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) {
|
|
goto recover;
|
|
}
|
|
if (buffer_new(bh)) {
|
|
/* blockdev mappings never come here */
|
|
clear_buffer_new(bh);
|
|
}
|
|
}
|
|
bh = bh->b_this_page;
|
|
block++;
|
|
} while (bh != head);
|
|
|
|
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) {
|
|
struct btrfs_trans_handle *trans;
|
|
int ret;
|
|
u64 off = page->index << PAGE_CACHE_SHIFT;
|
|
char *kaddr;
|
|
|
|
off += bh_offset(bh);
|
|
mutex_lock(&root->fs_info->fs_mutex);
|
|
trans = btrfs_start_transaction(root, 1);
|
|
btrfs_set_trans_block_group(trans, inode);
|
|
kaddr = kmap(page);
|
|
btrfs_csum_file_block(trans, root, inode->i_ino,
|
|
off, kaddr + bh_offset(bh),
|
|
bh->b_size);
|
|
kunmap(page);
|
|
ret = btrfs_end_transaction(trans, root);
|
|
BUG_ON(ret);
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
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;
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
/*
|
|
* btrfs_page_mkwrite() is not allowed to change the file size as it gets
|
|
* called from a page fault handler when a page is first dirtied. Hence we must
|
|
* be careful to check for EOF conditions here. We set the page up correctly
|
|
* for a written page which means we get ENOSPC checking when writing into
|
|
* holes and correct delalloc and unwritten extent mapping on filesystems that
|
|
* support these features.
|
|
*
|
|
* We are not allowed to take the i_mutex here so we have to play games to
|
|
* protect against truncate races as the page could now be beyond EOF. Because
|
|
* vmtruncate() writes the inode size before removing pages, once we have the
|
|
* page lock we can determine safely if the page is beyond EOF. If it is not
|
|
* beyond EOF, then the page is guaranteed safe against truncation until we
|
|
* unlock the page.
|
|
*/
|
|
int btrfs_page_mkwrite(struct vm_area_struct *vma, struct page *page)
|
|
{
|
|
struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
|
|
unsigned long end;
|
|
loff_t size;
|
|
int ret = -EINVAL;
|
|
|
|
lock_page(page);
|
|
wait_on_page_writeback(page);
|
|
size = i_size_read(inode);
|
|
if ((page->mapping != inode->i_mapping) ||
|
|
((page->index << PAGE_CACHE_SHIFT) > size)) {
|
|
/* page got truncated out from underneath us */
|
|
goto out_unlock;
|
|
}
|
|
|
|
/* page is wholly or partially inside EOF */
|
|
if (((page->index + 1) << PAGE_CACHE_SHIFT) > size)
|
|
end = size & ~PAGE_CACHE_MASK;
|
|
else
|
|
end = PAGE_CACHE_SIZE;
|
|
|
|
ret = btrfs_prepare_write(NULL, page, 0, end);
|
|
if (!ret)
|
|
ret = btrfs_commit_write(NULL, page, 0, end);
|
|
|
|
out_unlock:
|
|
unlock_page(page);
|
|
return ret;
|
|
}
|
|
|
|
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);
|
|
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);
|
|
}
|
|
|
|
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 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;
|
|
int err;
|
|
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, 0);
|
|
if (IS_ERR(subvol))
|
|
return PTR_ERR(subvol);
|
|
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));
|
|
btrfs_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);
|
|
memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
|
|
root_item.drop_level = 0;
|
|
brelse(subvol);
|
|
subvol = NULL;
|
|
|
|
ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
|
|
0, &objectid);
|
|
if (ret)
|
|
goto fail;
|
|
|
|
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);
|
|
if (ret)
|
|
goto fail;
|
|
|
|
/*
|
|
* 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);
|
|
if (ret)
|
|
goto fail;
|
|
|
|
ret = btrfs_commit_transaction(trans, root);
|
|
if (ret)
|
|
goto fail_commit;
|
|
|
|
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);
|
|
if (IS_ERR(inode))
|
|
goto fail;
|
|
inode->i_op = &btrfs_dir_inode_operations;
|
|
inode->i_fop = &btrfs_dir_file_operations;
|
|
new_root->inode = inode;
|
|
|
|
ret = btrfs_make_empty_dir(trans, new_root, new_dirid, new_dirid);
|
|
if (ret)
|
|
goto fail;
|
|
|
|
inode->i_nlink = 1;
|
|
inode->i_size = 6;
|
|
ret = btrfs_update_inode(trans, new_root, inode);
|
|
if (ret)
|
|
goto fail;
|
|
fail:
|
|
err = btrfs_commit_transaction(trans, root);
|
|
if (err && !ret)
|
|
ret = err;
|
|
fail_commit:
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
btrfs_btree_balance_dirty(root);
|
|
return ret;
|
|
}
|
|
|
|
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;
|
|
int err;
|
|
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);
|
|
if (ret)
|
|
goto fail;
|
|
|
|
ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
|
|
0, &objectid);
|
|
if (ret)
|
|
goto fail;
|
|
|
|
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);
|
|
if (ret)
|
|
goto fail;
|
|
|
|
/*
|
|
* 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);
|
|
|
|
if (ret)
|
|
goto fail;
|
|
|
|
ret = btrfs_inc_root_ref(trans, root);
|
|
if (ret)
|
|
goto fail;
|
|
|
|
fail:
|
|
err = btrfs_commit_transaction(trans, root);
|
|
if (err && !ret)
|
|
ret = err;
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
btrfs_btree_balance_dirty(root);
|
|
return ret;
|
|
}
|
|
|
|
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;
|
|
if (strchr(vol_args.name, '/'))
|
|
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 (IS_ERR(di))
|
|
return PTR_ERR(di);
|
|
|
|
if (root == root->fs_info->tree_root)
|
|
ret = create_subvol(root, vol_args.name, namelen);
|
|
else
|
|
ret = create_snapshot(root, vol_args.name, namelen);
|
|
break;
|
|
|
|
case BTRFS_IOC_DEFRAG:
|
|
mutex_lock(&root->fs_info->fs_mutex);
|
|
btrfs_defrag_root(root, 0);
|
|
btrfs_defrag_root(root->fs_info->extent_root, 0);
|
|
mutex_unlock(&root->fs_info->fs_mutex);
|
|
ret = 0;
|
|
break;
|
|
default:
|
|
return -ENOTTY;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
long btrfs_compat_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
int ret;
|
|
lock_kernel();
|
|
ret = btrfs_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
|
|
unlock_kernel();
|
|
return ret;
|
|
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Called inside transaction, so use GFP_NOFS
|
|
*/
|
|
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;
|
|
}
|
|
|
|
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;
|
|
|
|
inode_init_once(&ei->vfs_inode);
|
|
}
|
|
|
|
void btrfs_destroy_cachep(void)
|
|
{
|
|
if (btrfs_inode_cachep)
|
|
kmem_cache_destroy(btrfs_inode_cachep);
|
|
if (btrfs_trans_handle_cachep)
|
|
kmem_cache_destroy(btrfs_trans_handle_cachep);
|
|
if (btrfs_transaction_cachep)
|
|
kmem_cache_destroy(btrfs_transaction_cachep);
|
|
if (btrfs_bit_radix_cachep)
|
|
kmem_cache_destroy(btrfs_bit_radix_cachep);
|
|
if (btrfs_path_cachep)
|
|
kmem_cache_destroy(btrfs_path_cachep);
|
|
}
|
|
|
|
static struct kmem_cache *cache_create(const char *name, size_t size,
|
|
unsigned long extra_flags,
|
|
void (*ctor)(void *, struct kmem_cache *,
|
|
unsigned long))
|
|
{
|
|
return kmem_cache_create(name, size, 0, (SLAB_RECLAIM_ACCOUNT |
|
|
SLAB_MEM_SPREAD | extra_flags), ctor
|
|
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,23)
|
|
,NULL
|
|
#endif
|
|
);
|
|
}
|
|
|
|
int btrfs_init_cachep(void)
|
|
{
|
|
btrfs_inode_cachep = cache_create("btrfs_inode_cache",
|
|
sizeof(struct btrfs_inode),
|
|
0, init_once);
|
|
if (!btrfs_inode_cachep)
|
|
goto fail;
|
|
btrfs_trans_handle_cachep = cache_create("btrfs_trans_handle_cache",
|
|
sizeof(struct btrfs_trans_handle),
|
|
0, NULL);
|
|
if (!btrfs_trans_handle_cachep)
|
|
goto fail;
|
|
btrfs_transaction_cachep = cache_create("btrfs_transaction_cache",
|
|
sizeof(struct btrfs_transaction),
|
|
0, NULL);
|
|
if (!btrfs_transaction_cachep)
|
|
goto fail;
|
|
btrfs_path_cachep = cache_create("btrfs_path_cache",
|
|
sizeof(struct btrfs_transaction),
|
|
0, NULL);
|
|
if (!btrfs_path_cachep)
|
|
goto fail;
|
|
btrfs_bit_radix_cachep = cache_create("btrfs_radix", 256,
|
|
SLAB_DESTROY_BY_RCU, NULL);
|
|
if (!btrfs_bit_radix_cachep)
|
|
goto fail;
|
|
return 0;
|
|
fail:
|
|
btrfs_destroy_cachep();
|
|
return -ENOMEM;
|
|
}
|
|
|
|
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_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) {
|
|
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) {
|
|
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);
|
|
ret = btrfs_update_inode(trans, root, new_inode);
|
|
if (ret)
|
|
goto out_fail;
|
|
}
|
|
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);
|
|
if (err) {
|
|
drop_inode = 1;
|
|
goto out_unlock;
|
|
}
|
|
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);
|
|
btrfs_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;
|
|
err = btrfs_update_inode(trans, root, inode);
|
|
if (err)
|
|
drop_inode = 1;
|
|
|
|
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 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,
|
|
.mknod = btrfs_mknod,
|
|
};
|
|
|
|
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,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = btrfs_compat_ioctl,
|
|
#endif
|
|
};
|
|
|
|
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 inode_operations btrfs_special_inode_operations = {
|
|
.getattr = btrfs_getattr,
|
|
.setattr = btrfs_setattr,
|
|
};
|
|
|
|
static struct inode_operations btrfs_symlink_inode_operations = {
|
|
.readlink = generic_readlink,
|
|
.follow_link = page_follow_link_light,
|
|
.put_link = page_put_link,
|
|
};
|