13 files changed, 696 insertions, 19 deletions

diff --git a/fs/squashfs/Kconfig b/fs/squashfs/Kconfig
index 25a00d19d686..cc6ce8a84c21 100644
--- a/fs/squashfs/Kconfig
+++ b/fs/squashfs/Kconfig
@@ -26,6 +26,17 @@ config SQUASHFS
 
           If unsure, say N.
 
+config SQUASHFS_XATTRS
+        bool "Squashfs XATTR support"
+        depends on SQUASHFS
+        default n
+        help
+          Saying Y here includes support for extended attributes (xattrs).
+          Xattrs are name:value pairs associated with inodes by
+          the kernel or by users (see the attr(5) manual page).
+
+          If unsure, say N.
+
 config SQUASHFS_EMBEDDED
 
         bool "Additional option for memory-constrained systems" 
diff --git a/fs/squashfs/Makefile b/fs/squashfs/Makefile
index df8a19ef870d..2cee3e9fa452 100644
--- a/fs/squashfs/Makefile
+++ b/fs/squashfs/Makefile
@@ -5,3 +5,5 @@
 obj-$(CONFIG_SQUASHFS) += squashfs.o
 squashfs-y += block.o cache.o dir.o export.o file.o fragment.o id.o inode.o
 squashfs-y += namei.o super.o symlink.o zlib_wrapper.o decompressor.o
+squashfs-$(CONFIG_SQUASHFS_XATTRS) += xattr.o xattr_id.o
+
diff --git a/fs/squashfs/inode.c b/fs/squashfs/inode.c
index 49daaf669e41..62e63ad25075 100644
--- a/fs/squashfs/inode.c
+++ b/fs/squashfs/inode.c
@@ -40,11 +40,13 @@
 
 #include <linux/fs.h>
 #include <linux/vfs.h>
+#include <linux/xattr.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
 #include "squashfs_fs_i.h"
 #include "squashfs.h"
+#include "xattr.h"
 
 /*
  * Initialise VFS inode with the base inode information common to all
@@ -111,6 +113,7 @@ int squashfs_read_inode(struct inode *inode, long long ino)
         int err, type, offset = SQUASHFS_INODE_OFFSET(ino);
         union squashfs_inode squashfs_ino;
         struct squashfs_base_inode *sqshb_ino = &squashfs_ino.base;
+        int xattr_id = SQUASHFS_INVALID_XATTR;
 
         TRACE("Entered squashfs_read_inode\n");
 
@@ -199,8 +202,10 @@ int squashfs_read_inode(struct inode *inode, long long ino)
                         frag_offset = 0;
                 }
 
+                xattr_id = le32_to_cpu(sqsh_ino->xattr);
                 inode->i_nlink = le32_to_cpu(sqsh_ino->nlink);
                 inode->i_size = le64_to_cpu(sqsh_ino->file_size);
+                inode->i_op = &squashfs_inode_ops;
                 inode->i_fop = &generic_ro_fops;
                 inode->i_mode |= S_IFREG;
                 inode->i_blocks = ((inode->i_size -
@@ -251,6 +256,7 @@ int squashfs_read_inode(struct inode *inode, long long ino)
                 if (err < 0)
                         goto failed_read;
 
+                xattr_id = le32_to_cpu(sqsh_ino->xattr);
                 inode->i_nlink = le32_to_cpu(sqsh_ino->nlink);
                 inode->i_size = le32_to_cpu(sqsh_ino->file_size);
                 inode->i_op = &squashfs_dir_inode_ops;
@@ -280,21 +286,33 @@ int squashfs_read_inode(struct inode *inode, long long ino)
 
                 inode->i_nlink = le32_to_cpu(sqsh_ino->nlink);
                 inode->i_size = le32_to_cpu(sqsh_ino->symlink_size);
-                inode->i_op = &page_symlink_inode_operations;
+                inode->i_op = &squashfs_symlink_inode_ops;
                 inode->i_data.a_ops = &squashfs_symlink_aops;
                 inode->i_mode |= S_IFLNK;
                 squashfs_i(inode)->start = block;
                 squashfs_i(inode)->offset = offset;
 
+                if (type == SQUASHFS_LSYMLINK_TYPE) {
+                        __le32 xattr;
+
+                        err = squashfs_read_metadata(sb, NULL, &block,
+                                                &offset, inode->i_size);
+                        if (err < 0)
+                                goto failed_read;
+                        err = squashfs_read_metadata(sb, &xattr, &block,
+                                                &offset, sizeof(xattr));
+                        if (err < 0)
+                                goto failed_read;
+                        xattr_id = le32_to_cpu(xattr);
+                }
+
                 TRACE("Symbolic link inode %x:%x, start_block %llx, offset "
                                 "%x\n", SQUASHFS_INODE_BLK(ino), offset,
                                 block, offset);
                 break;
         }
         case SQUASHFS_BLKDEV_TYPE:
-        case SQUASHFS_CHRDEV_TYPE:
-        case SQUASHFS_LBLKDEV_TYPE:
-        case SQUASHFS_LCHRDEV_TYPE: {
+        case SQUASHFS_CHRDEV_TYPE: {
                 struct squashfs_dev_inode *sqsh_ino = &squashfs_ino.dev;
                 unsigned int rdev;
 
@@ -315,10 +333,32 @@ int squashfs_read_inode(struct inode *inode, long long ino)
                                 SQUASHFS_INODE_BLK(ino), offset, rdev);
                 break;
         }
+        case SQUASHFS_LBLKDEV_TYPE:
+        case SQUASHFS_LCHRDEV_TYPE: {
+                struct squashfs_ldev_inode *sqsh_ino = &squashfs_ino.ldev;
+                unsigned int rdev;
+
+                err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+                                sizeof(*sqsh_ino));
+                if (err < 0)
+                        goto failed_read;
+
+                if (type == SQUASHFS_LCHRDEV_TYPE)
+                        inode->i_mode |= S_IFCHR;
+                else
+                        inode->i_mode |= S_IFBLK;
+                xattr_id = le32_to_cpu(sqsh_ino->xattr);
+                inode->i_op = &squashfs_inode_ops;
+                inode->i_nlink = le32_to_cpu(sqsh_ino->nlink);
+                rdev = le32_to_cpu(sqsh_ino->rdev);
+                init_special_inode(inode, inode->i_mode, new_decode_dev(rdev));
+
+                TRACE("Device inode %x:%x, rdev %x\n",
+                                SQUASHFS_INODE_BLK(ino), offset, rdev);
+                break;
+        }
         case SQUASHFS_FIFO_TYPE:
-        case SQUASHFS_SOCKET_TYPE:
-        case SQUASHFS_LFIFO_TYPE:
-        case SQUASHFS_LSOCKET_TYPE: {
+        case SQUASHFS_SOCKET_TYPE: {
                 struct squashfs_ipc_inode *sqsh_ino = &squashfs_ino.ipc;
 
                 err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
@@ -334,14 +374,52 @@ int squashfs_read_inode(struct inode *inode, long long ino)
                 init_special_inode(inode, inode->i_mode, 0);
                 break;
         }
+        case SQUASHFS_LFIFO_TYPE:
+        case SQUASHFS_LSOCKET_TYPE: {
+                struct squashfs_lipc_inode *sqsh_ino = &squashfs_ino.lipc;
+
+                err = squashfs_read_metadata(sb, sqsh_ino, &block, &offset,
+                                sizeof(*sqsh_ino));
+                if (err < 0)
+                        goto failed_read;
+
+                if (type == SQUASHFS_LFIFO_TYPE)
+                        inode->i_mode |= S_IFIFO;
+                else
+                        inode->i_mode |= S_IFSOCK;
+                xattr_id = le32_to_cpu(sqsh_ino->xattr);
+                inode->i_op = &squashfs_inode_ops;
+                inode->i_nlink = le32_to_cpu(sqsh_ino->nlink);
+                init_special_inode(inode, inode->i_mode, 0);
+                break;
+        }
         default:
                 ERROR("Unknown inode type %d in squashfs_iget!\n", type);
                 return -EINVAL;
         }
 
+        if (xattr_id != SQUASHFS_INVALID_XATTR && msblk->xattr_id_table) {
+                err = squashfs_xattr_lookup(sb, xattr_id,
+                                        &squashfs_i(inode)->xattr_count,
+                                        &squashfs_i(inode)->xattr_size,
+                                        &squashfs_i(inode)->xattr);
+                if (err < 0)
+                        goto failed_read;
+                inode->i_blocks += ((squashfs_i(inode)->xattr_size - 1) >> 9)
+                                + 1;
+        } else
+                squashfs_i(inode)->xattr_count = 0;
+
         return 0;
 
 failed_read:
         ERROR("Unable to read inode 0x%llx\n", ino);
         return err;
 }
+
+
+const struct inode_operations squashfs_inode_ops = {
+        .getxattr = generic_getxattr,
+        .listxattr = squashfs_listxattr
+};
+
diff --git a/fs/squashfs/namei.c b/fs/squashfs/namei.c
index 5266bd8ad932..7a9464d08cf6 100644
--- a/fs/squashfs/namei.c
+++ b/fs/squashfs/namei.c
@@ -57,11 +57,13 @@
 #include <linux/slab.h>
 #include <linux/string.h>
 #include <linux/dcache.h>
+#include <linux/xattr.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
 #include "squashfs_fs_i.h"
 #include "squashfs.h"
+#include "xattr.h"
 
 /*
  * Lookup name in the directory index, returning the location of the metadata
@@ -237,5 +239,7 @@ failed:
 
 
 const struct inode_operations squashfs_dir_inode_ops = {
-        .lookup = squashfs_lookup
+        .lookup = squashfs_lookup,
+        .getxattr = generic_getxattr,
+        .listxattr = squashfs_listxattr
 };
diff --git a/fs/squashfs/squashfs.h b/fs/squashfs/squashfs.h
index fe2587af5512..733a17c42945 100644
--- a/fs/squashfs/squashfs.h
+++ b/fs/squashfs/squashfs.h
@@ -73,8 +73,11 @@ extern struct inode *squashfs_iget(struct super_block *, long long,
                                 unsigned int);
 extern int squashfs_read_inode(struct inode *, long long);
 
+/* xattr.c */
+extern ssize_t squashfs_listxattr(struct dentry *, char *, size_t);
+
 /*
- * Inodes, files and decompressor operations
+ * Inodes, files,  decompressor and xattr operations
  */
 
 /* dir.c */
@@ -86,11 +89,18 @@ extern const struct export_operations squashfs_export_ops;
 /* file.c */
 extern const struct address_space_operations squashfs_aops;
 
+/* inode.c */
+extern const struct inode_operations squashfs_inode_ops;
+
 /* namei.c */
 extern const struct inode_operations squashfs_dir_inode_ops;
 
 /* symlink.c */
 extern const struct address_space_operations squashfs_symlink_aops;
+extern const struct inode_operations squashfs_symlink_inode_ops;
+
+/* xattr.c */
+extern const struct xattr_handler *squashfs_xattr_handlers[];
 
 /* zlib_wrapper.c */
 extern const struct squashfs_decompressor squashfs_zlib_comp_ops;
diff --git a/fs/squashfs/squashfs_fs.h b/fs/squashfs/squashfs_fs.h
index 79024245ea00..8eabb808b78d 100644
--- a/fs/squashfs/squashfs_fs.h
+++ b/fs/squashfs/squashfs_fs.h
@@ -46,6 +46,7 @@
 #define SQUASHFS_NAME_LEN               256
 
 #define SQUASHFS_INVALID_FRAG           (0xffffffffU)
+#define SQUASHFS_INVALID_XATTR          (0xffffffffU)
 #define SQUASHFS_INVALID_BLK            (-1LL)
 
 /* Filesystem flags */
@@ -96,6 +97,13 @@
 #define SQUASHFS_LFIFO_TYPE             13
 #define SQUASHFS_LSOCKET_TYPE           14
 
+/* Xattr types */
+#define SQUASHFS_XATTR_USER             0
+#define SQUASHFS_XATTR_TRUSTED          1
+#define SQUASHFS_XATTR_SECURITY         2
+#define SQUASHFS_XATTR_VALUE_OOL        256
+#define SQUASHFS_XATTR_PREFIX_MASK      0xff
+
 /* Flag whether block is compressed or uncompressed, bit is set if block is
  * uncompressed */
 #define SQUASHFS_COMPRESSED_BIT         (1 << 15)
@@ -174,6 +182,24 @@
 
 #define SQUASHFS_ID_BLOCK_BYTES(A)      (SQUASHFS_ID_BLOCKS(A) *\
                                         sizeof(u64))
+/* xattr id lookup table defines */
+#define SQUASHFS_XATTR_BYTES(A)         ((A) * sizeof(struct squashfs_xattr_id))
+
+#define SQUASHFS_XATTR_BLOCK(A)         (SQUASHFS_XATTR_BYTES(A) / \
+                                        SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_XATTR_BLOCK_OFFSET(A)  (SQUASHFS_XATTR_BYTES(A) % \
+                                        SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_XATTR_BLOCKS(A)        ((SQUASHFS_XATTR_BYTES(A) + \
+                                        SQUASHFS_METADATA_SIZE - 1) / \
+                                        SQUASHFS_METADATA_SIZE)
+
+#define SQUASHFS_XATTR_BLOCK_BYTES(A)   (SQUASHFS_XATTR_BLOCKS(A) *\
+                                        sizeof(u64))
+#define SQUASHFS_XATTR_BLK(A)           ((unsigned int) ((A) >> 16))
+
+#define SQUASHFS_XATTR_OFFSET(A)        ((unsigned int) ((A) & 0xffff))
 
 /* cached data constants for filesystem */
 #define SQUASHFS_CACHED_BLKS            8
@@ -228,7 +254,7 @@ struct squashfs_super_block {
         __le64                  root_inode;
         __le64                  bytes_used;
         __le64                  id_table_start;
-        __le64                  xattr_table_start;
+        __le64                  xattr_id_table_start;
         __le64                  inode_table_start;
         __le64                  directory_table_start;
         __le64                  fragment_table_start;
@@ -261,6 +287,17 @@ struct squashfs_ipc_inode {
         __le32                  nlink;
 };
 
+struct squashfs_lipc_inode {
+        __le16                  inode_type;
+        __le16                  mode;
+        __le16                  uid;
+        __le16                  guid;
+        __le32                  mtime;
+        __le32                  inode_number;
+        __le32                  nlink;
+        __le32                  xattr;
+};
+
 struct squashfs_dev_inode {
         __le16                  inode_type;
         __le16                  mode;
@@ -272,6 +309,18 @@ struct squashfs_dev_inode {
         __le32                  rdev;
 };
 
+struct squashfs_ldev_inode {
+        __le16                  inode_type;
+        __le16                  mode;
+        __le16                  uid;
+        __le16                  guid;
+        __le32                  mtime;
+        __le32                  inode_number;
+        __le32                  nlink;
+        __le32                  rdev;
+        __le32                  xattr;
+};
+
 struct squashfs_symlink_inode {
         __le16                  inode_type;
         __le16                  mode;
@@ -349,12 +398,14 @@ struct squashfs_ldir_inode {
 union squashfs_inode {
         struct squashfs_base_inode              base;
         struct squashfs_dev_inode               dev;
+        struct squashfs_ldev_inode              ldev;
         struct squashfs_symlink_inode           symlink;
         struct squashfs_reg_inode               reg;
         struct squashfs_lreg_inode              lreg;
         struct squashfs_dir_inode               dir;
         struct squashfs_ldir_inode              ldir;
         struct squashfs_ipc_inode               ipc;
+        struct squashfs_lipc_inode              lipc;
 };
 
 struct squashfs_dir_entry {
@@ -377,4 +428,27 @@ struct squashfs_fragment_entry {
         unsigned int            unused;
 };
 
+struct squashfs_xattr_entry {
+        __le16                  type;
+        __le16                  size;
+        char                    data[0];
+};
+
+struct squashfs_xattr_val {
+        __le32                  vsize;
+        char                    value[0];
+};
+
+struct squashfs_xattr_id {
+        __le64                  xattr;
+        __le32                  count;
+        __le32                  size;
+};
+
+struct squashfs_xattr_id_table {
+        __le64                  xattr_table_start;
+        __le32                  xattr_ids;
+        __le32                  unused;
+};
+
 #endif
diff --git a/fs/squashfs/squashfs_fs_i.h b/fs/squashfs/squashfs_fs_i.h
index fbfca30c0c68..d3e3a37f28a1 100644
--- a/fs/squashfs/squashfs_fs_i.h
+++ b/fs/squashfs/squashfs_fs_i.h
@@ -26,6 +26,9 @@
 struct squashfs_inode_info {
         u64             start;
         int             offset;
+        u64             xattr;
+        unsigned int    xattr_size;
+        int             xattr_count;
         union {
                 struct {
                         u64             fragment_block;
diff --git a/fs/squashfs/squashfs_fs_sb.h b/fs/squashfs/squashfs_fs_sb.h
index 2e77dc547e25..d9037a5215f0 100644
--- a/fs/squashfs/squashfs_fs_sb.h
+++ b/fs/squashfs/squashfs_fs_sb.h
@@ -61,6 +61,7 @@ struct squashfs_sb_info {
         int                                     next_meta_index;
         __le64                                  *id_table;
         __le64                                  *fragment_index;
+        __le64                                  *xattr_id_table;
         struct mutex                            read_data_mutex;
         struct mutex                            meta_index_mutex;
         struct meta_index                       *meta_index;
@@ -68,9 +69,11 @@ struct squashfs_sb_info {
         __le64                                  *inode_lookup_table;
         u64                                     inode_table;
         u64                                     directory_table;
+        u64                                     xattr_table;
         unsigned int                            block_size;
         unsigned short                          block_log;
         long long                               bytes_used;
         unsigned int                            inodes;
+        int                                     xattr_ids;
 };
 #endif
diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c
index 48b6f4a385a6..88b4f8606652 100644
--- a/fs/squashfs/super.c
+++ b/fs/squashfs/super.c
@@ -36,12 +36,14 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/magic.h>
+#include <linux/xattr.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
 #include "squashfs_fs_i.h"
 #include "squashfs.h"
 #include "decompressor.h"
+#include "xattr.h"
 
 static struct file_system_type squashfs_fs_type;
 static const struct super_operations squashfs_super_ops;
@@ -82,7 +84,7 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
         long long root_inode;
         unsigned short flags;
         unsigned int fragments;
-        u64 lookup_table_start;
+        u64 lookup_table_start, xattr_id_table_start;
         int err;
 
         TRACE("Entered squashfs_fill_superblock\n");
@@ -139,13 +141,6 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
         if (msblk->decompressor == NULL)
                 goto failed_mount;
 
-        /*
-         * Check if there's xattrs in the filesystem.  These are not
-         * supported in this version, so warn that they will be ignored.
-         */
-        if (le64_to_cpu(sblk->xattr_table_start) != SQUASHFS_INVALID_BLK)
-                ERROR("Xattrs in filesystem, these will be ignored\n");
-
         /* Check the filesystem does not extend beyond the end of the
            block device */
         msblk->bytes_used = le64_to_cpu(sblk->bytes_used);
@@ -253,7 +248,7 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
 allocate_lookup_table:
         lookup_table_start = le64_to_cpu(sblk->lookup_table_start);
         if (lookup_table_start == SQUASHFS_INVALID_BLK)
-                goto allocate_root;
+                goto allocate_xattr_table;
 
         /* Allocate and read inode lookup table */
         msblk->inode_lookup_table = squashfs_read_inode_lookup_table(sb,
@@ -266,6 +261,21 @@ allocate_lookup_table:
 
         sb->s_export_op = &squashfs_export_ops;
 
+allocate_xattr_table:
+        sb->s_xattr = squashfs_xattr_handlers;
+        xattr_id_table_start = le64_to_cpu(sblk->xattr_id_table_start);
+        if (xattr_id_table_start == SQUASHFS_INVALID_BLK)
+                goto allocate_root;
+
+        /* Allocate and read xattr id lookup table */
+        msblk->xattr_id_table = squashfs_read_xattr_id_table(sb,
+                xattr_id_table_start, &msblk->xattr_table, &msblk->xattr_ids);
+        if (IS_ERR(msblk->xattr_id_table)) {
+                err = PTR_ERR(msblk->xattr_id_table);
+                msblk->xattr_id_table = NULL;
+                if (err != -ENOTSUPP)
+                        goto failed_mount;
+        }
 allocate_root:
         root = new_inode(sb);
         if (!root) {
@@ -301,6 +311,7 @@ failed_mount:
         kfree(msblk->inode_lookup_table);
         kfree(msblk->fragment_index);
         kfree(msblk->id_table);
+        kfree(msblk->xattr_id_table);
         kfree(sb->s_fs_info);
         sb->s_fs_info = NULL;
         kfree(sblk);
@@ -355,6 +366,7 @@ static void squashfs_put_super(struct super_block *sb)
                 kfree(sbi->fragment_index);
                 kfree(sbi->meta_index);
                 kfree(sbi->inode_lookup_table);
+                kfree(sbi->xattr_id_table);
                 kfree(sb->s_fs_info);
                 sb->s_fs_info = NULL;
         }
diff --git a/fs/squashfs/symlink.c b/fs/squashfs/symlink.c
index 32b911f4ee39..ec86434921e1 100644
--- a/fs/squashfs/symlink.c
+++ b/fs/squashfs/symlink.c
@@ -35,11 +35,13 @@
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/pagemap.h>
+#include <linux/xattr.h>
 
 #include "squashfs_fs.h"
 #include "squashfs_fs_sb.h"
 #include "squashfs_fs_i.h"
 #include "squashfs.h"
+#include "xattr.h"
 
 static int squashfs_symlink_readpage(struct file *file, struct page *page)
 {
@@ -114,3 +116,12 @@ error_out:
 const struct address_space_operations squashfs_symlink_aops = {
         .readpage = squashfs_symlink_readpage
 };
+
+const struct inode_operations squashfs_symlink_inode_ops = {
+        .readlink = generic_readlink,
+        .follow_link = page_follow_link_light,
+        .put_link = page_put_link,
+        .getxattr = generic_getxattr,
+        .listxattr = squashfs_listxattr
+};
+
diff --git a/fs/squashfs/xattr.c b/fs/squashfs/xattr.c
new file mode 100644
index 000000000000..c7655e8b31cd
--- /dev/null
+++ b/fs/squashfs/xattr.c
@@ -0,0 +1,323 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2010
+ * Phillip Lougher <phillip@lougher.demon.co.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.
+ *
+ * xattr_id.c
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/fs.h>
+#include <linux/vfs.h>
+#include <linux/xattr.h>
+#include <linux/slab.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+
+static const struct xattr_handler *squashfs_xattr_handler(int);
+
+ssize_t squashfs_listxattr(struct dentry *d, char *buffer,
+        size_t buffer_size)
+{
+        struct inode *inode = d->d_inode;
+        struct super_block *sb = inode->i_sb;
+        struct squashfs_sb_info *msblk = sb->s_fs_info;
+        u64 start = SQUASHFS_XATTR_BLK(squashfs_i(inode)->xattr)
+                                                 + msblk->xattr_table;
+        int offset = SQUASHFS_XATTR_OFFSET(squashfs_i(inode)->xattr);
+        int count = squashfs_i(inode)->xattr_count;
+        size_t rest = buffer_size;
+        int err;
+
+        /* check that the file system has xattrs */
+        if (msblk->xattr_id_table == NULL)
+                return -EOPNOTSUPP;
+
+        /* loop reading each xattr name */
+        while (count--) {
+                struct squashfs_xattr_entry entry;
+                struct squashfs_xattr_val val;
+                const struct xattr_handler *handler;
+                int name_size, prefix_size = 0;
+
+                err = squashfs_read_metadata(sb, &entry, &start, &offset,
+                                                        sizeof(entry));
+                if (err < 0)
+                        goto failed;
+
+                name_size = le16_to_cpu(entry.size);
+                handler = squashfs_xattr_handler(le16_to_cpu(entry.type));
+                if (handler)
+                        prefix_size = handler->list(d, buffer, rest, NULL,
+                                name_size, handler->flags);
+                if (prefix_size) {
+                        if (buffer) {
+                                if (prefix_size + name_size + 1 > rest) {
+                                        err = -ERANGE;
+                                        goto failed;
+                                }
+                                buffer += prefix_size;
+                        }
+                        err = squashfs_read_metadata(sb, buffer, &start,
+                                &offset, name_size);
+                        if (err < 0)
+                                goto failed;
+                        if (buffer) {
+                                buffer[name_size] = '\0';
+                                buffer += name_size + 1;
+                        }
+                        rest -= prefix_size + name_size + 1;
+                } else  {
+                        /* no handler or insuffficient privileges, so skip */
+                        err = squashfs_read_metadata(sb, NULL, &start,
+                                &offset, name_size);
+                        if (err < 0)
+                                goto failed;
+                }
+
+
+                /* skip remaining xattr entry */
+                err = squashfs_read_metadata(sb, &val, &start, &offset,
+                                                sizeof(val));
+                if (err < 0)
+                        goto failed;
+
+                err = squashfs_read_metadata(sb, NULL, &start, &offset,
+                                                le32_to_cpu(val.vsize));
+                if (err < 0)
+                        goto failed;
+        }
+        err = buffer_size - rest;
+
+failed:
+        return err;
+}
+
+
+static int squashfs_xattr_get(struct inode *inode, int name_index,
+        const char *name, void *buffer, size_t buffer_size)
+{
+        struct super_block *sb = inode->i_sb;
+        struct squashfs_sb_info *msblk = sb->s_fs_info;
+        u64 start = SQUASHFS_XATTR_BLK(squashfs_i(inode)->xattr)
+                                                 + msblk->xattr_table;
+        int offset = SQUASHFS_XATTR_OFFSET(squashfs_i(inode)->xattr);
+        int count = squashfs_i(inode)->xattr_count;
+        int name_len = strlen(name);
+        int err, vsize;
+        char *target = kmalloc(name_len, GFP_KERNEL);
+
+        if (target == NULL)
+                return  -ENOMEM;
+
+        /* loop reading each xattr name */
+        for (; count; count--) {
+                struct squashfs_xattr_entry entry;
+                struct squashfs_xattr_val val;
+                int type, prefix, name_size;
+
+                err = squashfs_read_metadata(sb, &entry, &start, &offset,
+                                                        sizeof(entry));
+                if (err < 0)
+                        goto failed;
+
+                name_size = le16_to_cpu(entry.size);
+                type = le16_to_cpu(entry.type);
+                prefix = type & SQUASHFS_XATTR_PREFIX_MASK;
+
+                if (prefix == name_index && name_size == name_len)
+                        err = squashfs_read_metadata(sb, target, &start,
+                                                &offset, name_size);
+                else
+                        err = squashfs_read_metadata(sb, NULL, &start,
+                                                &offset, name_size);
+                if (err < 0)
+                        goto failed;
+
+                if (prefix == name_index && name_size == name_len &&
+                                        strncmp(target, name, name_size) == 0) {
+                        /* found xattr */
+                        if (type & SQUASHFS_XATTR_VALUE_OOL) {
+                                __le64 xattr;
+                                /* val is a reference to the real location */
+                                err = squashfs_read_metadata(sb, &val, &start,
+                                                &offset, sizeof(val));
+                                if (err < 0)
+                                        goto failed;
+                                err = squashfs_read_metadata(sb, &xattr, &start,
+                                         &offset, sizeof(xattr));
+                                if (err < 0)
+                                        goto failed;
+                                xattr = le64_to_cpu(xattr);
+                                start = SQUASHFS_XATTR_BLK(xattr) +
+                                                        msblk->xattr_table;
+                                offset = SQUASHFS_XATTR_OFFSET(xattr);
+                        }
+                        /* read xattr value */
+                        err = squashfs_read_metadata(sb, &val, &start, &offset,
+                                                        sizeof(val));
+                        if (err < 0)
+                                goto failed;
+
+                        vsize = le32_to_cpu(val.vsize);
+                        if (buffer) {
+                                if (vsize > buffer_size) {
+                                        err = -ERANGE;
+                                        goto failed;
+                                }
+                                err = squashfs_read_metadata(sb, buffer, &start,
+                                         &offset, vsize);
+                                if (err < 0)
+                                        goto failed;
+                        }
+                        break;
+                }
+
+                /* no match, skip remaining xattr entry */
+                err = squashfs_read_metadata(sb, &val, &start, &offset,
+                                                        sizeof(val));
+                if (err < 0)
+                        goto failed;
+                err = squashfs_read_metadata(sb, NULL, &start, &offset,
+                                                le32_to_cpu(val.vsize));
+                if (err < 0)
+                        goto failed;
+        }
+        err = count ? vsize : -ENODATA;
+
+failed:
+        kfree(target);
+        return err;
+}
+
+
+/*
+ * User namespace support
+ */
+static size_t squashfs_user_list(struct dentry *d, char *list, size_t list_size,
+        const char *name, size_t name_len, int type)
+{
+        if (list && XATTR_USER_PREFIX_LEN <= list_size)
+                memcpy(list, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
+        return XATTR_USER_PREFIX_LEN;
+}
+
+static int squashfs_user_get(struct dentry *d, const char *name, void *buffer,
+        size_t size, int type)
+{
+        if (name[0] == '\0')
+                return  -EINVAL;
+
+        return squashfs_xattr_get(d->d_inode, SQUASHFS_XATTR_USER, name,
+                buffer, size);
+}
+
+static const struct xattr_handler squashfs_xattr_user_handler = {
+        .prefix = XATTR_USER_PREFIX,
+        .list   = squashfs_user_list,
+        .get    = squashfs_user_get
+};
+
+/*
+ * Trusted namespace support
+ */
+static size_t squashfs_trusted_list(struct dentry *d, char *list,
+        size_t list_size, const char *name, size_t name_len, int type)
+{
+        if (!capable(CAP_SYS_ADMIN))
+                return 0;
+
+        if (list && XATTR_TRUSTED_PREFIX_LEN <= list_size)
+                memcpy(list, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN);
+        return XATTR_TRUSTED_PREFIX_LEN;
+}
+
+static int squashfs_trusted_get(struct dentry *d, const char *name,
+        void *buffer, size_t size, int type)
+{
+        if (name[0] == '\0')
+                return  -EINVAL;
+
+        return squashfs_xattr_get(d->d_inode, SQUASHFS_XATTR_TRUSTED, name,
+                buffer, size);
+}
+
+static const struct xattr_handler squashfs_xattr_trusted_handler = {
+        .prefix = XATTR_TRUSTED_PREFIX,
+        .list   = squashfs_trusted_list,
+        .get    = squashfs_trusted_get
+};
+
+/*
+ * Security namespace support
+ */
+static size_t squashfs_security_list(struct dentry *d, char *list,
+        size_t list_size, const char *name, size_t name_len, int type)
+{
+        if (list && XATTR_SECURITY_PREFIX_LEN <= list_size)
+                memcpy(list, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN);
+        return XATTR_SECURITY_PREFIX_LEN;
+}
+
+static int squashfs_security_get(struct dentry *d, const char *name,
+        void *buffer, size_t size, int type)
+{
+        if (name[0] == '\0')
+                return  -EINVAL;
+
+        return squashfs_xattr_get(d->d_inode, SQUASHFS_XATTR_SECURITY, name,
+                buffer, size);
+}
+
+static const struct xattr_handler squashfs_xattr_security_handler = {
+        .prefix = XATTR_SECURITY_PREFIX,
+        .list   = squashfs_security_list,
+        .get    = squashfs_security_get
+};
+
+static inline const struct xattr_handler *squashfs_xattr_handler(int type)
+{
+        if (type & ~(SQUASHFS_XATTR_PREFIX_MASK | SQUASHFS_XATTR_VALUE_OOL))
+                /* ignore unrecognised type */
+                return NULL;
+
+        switch (type & SQUASHFS_XATTR_PREFIX_MASK) {
+        case SQUASHFS_XATTR_USER:
+                return &squashfs_xattr_user_handler;
+        case SQUASHFS_XATTR_TRUSTED:
+                return &squashfs_xattr_trusted_handler;
+        case SQUASHFS_XATTR_SECURITY:
+                return &squashfs_xattr_security_handler;
+        default:
+                /* ignore unrecognised type */
+                return NULL;
+        }
+}
+
+const struct xattr_handler *squashfs_xattr_handlers[] = {
+        &squashfs_xattr_user_handler,
+        &squashfs_xattr_trusted_handler,
+        &squashfs_xattr_security_handler,
+        NULL
+};
+
diff --git a/fs/squashfs/xattr.h b/fs/squashfs/xattr.h
new file mode 100644
index 000000000000..9da071ae181c
--- /dev/null
+++ b/fs/squashfs/xattr.h
@@ -0,0 +1,46 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2010
+ * Phillip Lougher <phillip@lougher.demon.co.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.
+ *
+ * xattr.h
+ */
+
+#ifdef CONFIG_SQUASHFS_XATTRS
+extern __le64 *squashfs_read_xattr_id_table(struct super_block *, u64,
+                u64 *, int *);
+extern int squashfs_xattr_lookup(struct super_block *, unsigned int, int *,
+                int *, unsigned long long *);
+#else
+static inline __le64 *squashfs_read_xattr_id_table(struct super_block *sb,
+                u64 start, u64 *xattr_table_start, int *xattr_ids)
+{
+        ERROR("Xattrs in filesystem, these will be ignored\n");
+        return ERR_PTR(-ENOTSUPP);
+}
+
+static inline int squashfs_xattr_lookup(struct super_block *sb,
+                unsigned int index, int *count, int *size,
+                unsigned long long *xattr)
+{
+        return 0;
+}
+#define squashfs_listxattr NULL
+#define generic_getxattr NULL
+#define squashfs_xattr_handlers NULL
+#endif
diff --git a/fs/squashfs/xattr_id.c b/fs/squashfs/xattr_id.c
new file mode 100644
index 000000000000..cfb41106098f
--- /dev/null
+++ b/fs/squashfs/xattr_id.c
@@ -0,0 +1,100 @@
+/*
+ * Squashfs - a compressed read only filesystem for Linux
+ *
+ * Copyright (c) 2010
+ * Phillip Lougher <phillip@lougher.demon.co.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.
+ *
+ * xattr_id.c
+ */
+
+/*
+ * This file implements code to map the 32-bit xattr id stored in the inode
+ * into the on disk location of the xattr data.
+ */
+
+#include <linux/fs.h>
+#include <linux/vfs.h>
+#include <linux/slab.h>
+
+#include "squashfs_fs.h"
+#include "squashfs_fs_sb.h"
+#include "squashfs_fs_i.h"
+#include "squashfs.h"
+
+/*
+ * Map xattr id using the xattr id look up table
+ */
+int squashfs_xattr_lookup(struct super_block *sb, unsigned int index,
+                int *count, unsigned int *size, unsigned long long *xattr)
+{
+        struct squashfs_sb_info *msblk = sb->s_fs_info;
+        int block = SQUASHFS_XATTR_BLOCK(index);
+        int offset = SQUASHFS_XATTR_BLOCK_OFFSET(index);
+        u64 start_block = le64_to_cpu(msblk->xattr_id_table[block]);
+        struct squashfs_xattr_id id;
+        int err;
+
+        err = squashfs_read_metadata(sb, &id, &start_block, &offset,
+                                                        sizeof(id));
+        if (err < 0)
+                return err;
+
+        *xattr = le64_to_cpu(id.xattr);
+        *size = le32_to_cpu(id.size);
+        *count = le32_to_cpu(id.count);
+        return 0;
+}
+
+
+/*
+ * Read uncompressed xattr id lookup table indexes from disk into memory
+ */
+__le64 *squashfs_read_xattr_id_table(struct super_block *sb, u64 start,
+                u64 *xattr_table_start, int *xattr_ids)
+{
+        unsigned int len;
+        __le64 *xid_table;
+        struct squashfs_xattr_id_table id_table;
+        int err;
+
+        err = squashfs_read_table(sb, &id_table, start, sizeof(id_table));
+        if (err < 0) {
+                ERROR("unable to read xattr id table\n");
+                return ERR_PTR(err);
+        }
+        *xattr_table_start = le64_to_cpu(id_table.xattr_table_start);
+        *xattr_ids = le32_to_cpu(id_table.xattr_ids);
+        len = SQUASHFS_XATTR_BLOCK_BYTES(*xattr_ids);
+
+        TRACE("In read_xattr_index_table, length %d\n", len);
+
+        /* Allocate xattr id lookup table indexes */
+        xid_table = kmalloc(len, GFP_KERNEL);
+        if (xid_table == NULL) {
+                ERROR("Failed to allocate xattr id index table\n");
+                return ERR_PTR(-ENOMEM);
+        }
+
+        err = squashfs_read_table(sb, xid_table, start + sizeof(id_table), len);
+        if (err < 0) {
+                ERROR("unable to read xattr id index table\n");
+                kfree(xid_table);
+                return ERR_PTR(err);
+        }
+
+        return xid_table;
+}