diff options
Diffstat (limited to 'ANDROID_3.4.5/fs/squashfs/export.c')
| -rw-r--r-- | ANDROID_3.4.5/fs/squashfs/export.c | 163 |
1 files changed, 0 insertions, 163 deletions
diff --git a/ANDROID_3.4.5/fs/squashfs/export.c b/ANDROID_3.4.5/fs/squashfs/export.c deleted file mode 100644 index 5e1101ff..00000000 --- a/ANDROID_3.4.5/fs/squashfs/export.c +++ /dev/null @@ -1,163 +0,0 @@ -/* - * Squashfs - a compressed read only filesystem for Linux - * - * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008 - * Phillip Lougher <phillip@squashfs.org.uk> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version 2, - * or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. - * - * export.c - */ - -/* - * This file implements code to make Squashfs filesystems exportable (NFS etc.) - * - * The export code uses an inode lookup table to map inode numbers passed in - * filehandles to an inode location on disk. This table is stored compressed - * into metadata blocks. A second index table is used to locate these. This - * second index table for speed of access (and because it is small) is read at - * mount time and cached in memory. - * - * The inode lookup table is used only by the export code, inode disk - * locations are directly encoded in directories, enabling direct access - * without an intermediate lookup for all operations except the export ops. - */ - -#include <linux/fs.h> -#include <linux/vfs.h> -#include <linux/dcache.h> -#include <linux/exportfs.h> -#include <linux/slab.h> - -#include "squashfs_fs.h" -#include "squashfs_fs_sb.h" -#include "squashfs_fs_i.h" -#include "squashfs.h" - -/* - * Look-up inode number (ino) in table, returning the inode location. - */ -static long long squashfs_inode_lookup(struct super_block *sb, int ino_num) -{ - struct squashfs_sb_info *msblk = sb->s_fs_info; - int blk = SQUASHFS_LOOKUP_BLOCK(ino_num - 1); - int offset = SQUASHFS_LOOKUP_BLOCK_OFFSET(ino_num - 1); - u64 start = le64_to_cpu(msblk->inode_lookup_table[blk]); - __le64 ino; - int err; - - TRACE("Entered squashfs_inode_lookup, inode_number = %d\n", ino_num); - - err = squashfs_read_metadata(sb, &ino, &start, &offset, sizeof(ino)); - if (err < 0) - return err; - - TRACE("squashfs_inode_lookup, inode = 0x%llx\n", - (u64) le64_to_cpu(ino)); - - return le64_to_cpu(ino); -} - - -static struct dentry *squashfs_export_iget(struct super_block *sb, - unsigned int ino_num) -{ - long long ino; - struct dentry *dentry = ERR_PTR(-ENOENT); - - TRACE("Entered squashfs_export_iget\n"); - - ino = squashfs_inode_lookup(sb, ino_num); - if (ino >= 0) - dentry = d_obtain_alias(squashfs_iget(sb, ino, ino_num)); - - return dentry; -} - - -static struct dentry *squashfs_fh_to_dentry(struct super_block *sb, - struct fid *fid, int fh_len, int fh_type) -{ - if ((fh_type != FILEID_INO32_GEN && fh_type != FILEID_INO32_GEN_PARENT) - || fh_len < 2) - return NULL; - - return squashfs_export_iget(sb, fid->i32.ino); -} - - -static struct dentry *squashfs_fh_to_parent(struct super_block *sb, - struct fid *fid, int fh_len, int fh_type) -{ - if (fh_type != FILEID_INO32_GEN_PARENT || fh_len < 4) - return NULL; - - return squashfs_export_iget(sb, fid->i32.parent_ino); -} - - -static struct dentry *squashfs_get_parent(struct dentry *child) -{ - struct inode *inode = child->d_inode; - unsigned int parent_ino = squashfs_i(inode)->parent; - - return squashfs_export_iget(inode->i_sb, parent_ino); -} - - -/* - * Read uncompressed inode lookup table indexes off disk into memory - */ -__le64 *squashfs_read_inode_lookup_table(struct super_block *sb, - u64 lookup_table_start, u64 next_table, unsigned int inodes) -{ - unsigned int length = SQUASHFS_LOOKUP_BLOCK_BYTES(inodes); - __le64 *table; - - TRACE("In read_inode_lookup_table, length %d\n", length); - - /* Sanity check values */ - - /* there should always be at least one inode */ - if (inodes == 0) - return ERR_PTR(-EINVAL); - - /* length bytes should not extend into the next table - this check - * also traps instances where lookup_table_start is incorrectly larger - * than the next table start - */ - if (lookup_table_start + length > next_table) - return ERR_PTR(-EINVAL); - - table = squashfs_read_table(sb, lookup_table_start, length); - - /* - * table[0] points to the first inode lookup table metadata block, - * this should be less than lookup_table_start - */ - if (!IS_ERR(table) && le64_to_cpu(table[0]) >= lookup_table_start) { - kfree(table); - return ERR_PTR(-EINVAL); - } - - return table; -} - - -const struct export_operations squashfs_export_ops = { - .fh_to_dentry = squashfs_fh_to_dentry, - .fh_to_parent = squashfs_fh_to_parent, - .get_parent = squashfs_get_parent -}; |