Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / hfsplus / xattr.c
diff --git a/kernel/fs/hfsplus/xattr.c b/kernel/fs/hfsplus/xattr.c
new file mode 100644 (file)
index 0000000..416b1db
--- /dev/null
@@ -0,0 +1,911 @@
+/*
+ * linux/fs/hfsplus/xattr.c
+ *
+ * Vyacheslav Dubeyko <slava@dubeyko.com>
+ *
+ * Logic of processing extended attributes
+ */
+
+#include "hfsplus_fs.h"
+#include <linux/posix_acl_xattr.h>
+#include <linux/nls.h>
+#include "xattr.h"
+#include "acl.h"
+
+static int hfsplus_removexattr(struct inode *inode, const char *name);
+
+const struct xattr_handler *hfsplus_xattr_handlers[] = {
+       &hfsplus_xattr_osx_handler,
+       &hfsplus_xattr_user_handler,
+       &hfsplus_xattr_trusted_handler,
+#ifdef CONFIG_HFSPLUS_FS_POSIX_ACL
+       &posix_acl_access_xattr_handler,
+       &posix_acl_default_xattr_handler,
+#endif
+       &hfsplus_xattr_security_handler,
+       NULL
+};
+
+static int strcmp_xattr_finder_info(const char *name)
+{
+       if (name) {
+               return strncmp(name, HFSPLUS_XATTR_FINDER_INFO_NAME,
+                               sizeof(HFSPLUS_XATTR_FINDER_INFO_NAME));
+       }
+       return -1;
+}
+
+static int strcmp_xattr_acl(const char *name)
+{
+       if (name) {
+               return strncmp(name, HFSPLUS_XATTR_ACL_NAME,
+                               sizeof(HFSPLUS_XATTR_ACL_NAME));
+       }
+       return -1;
+}
+
+static bool is_known_namespace(const char *name)
+{
+       if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) &&
+           strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
+           strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
+           strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN))
+               return false;
+
+       return true;
+}
+
+static void hfsplus_init_header_node(struct inode *attr_file,
+                                       u32 clump_size,
+                                       char *buf, u16 node_size)
+{
+       struct hfs_bnode_desc *desc;
+       struct hfs_btree_header_rec *head;
+       u16 offset;
+       __be16 *rec_offsets;
+       u32 hdr_node_map_rec_bits;
+       char *bmp;
+       u32 used_nodes;
+       u32 used_bmp_bytes;
+       u64 tmp;
+
+       hfs_dbg(ATTR_MOD, "init_hdr_attr_file: clump %u, node_size %u\n",
+               clump_size, node_size);
+
+       /* The end of the node contains list of record offsets */
+       rec_offsets = (__be16 *)(buf + node_size);
+
+       desc = (struct hfs_bnode_desc *)buf;
+       desc->type = HFS_NODE_HEADER;
+       desc->num_recs = cpu_to_be16(HFSPLUS_BTREE_HDR_NODE_RECS_COUNT);
+       offset = sizeof(struct hfs_bnode_desc);
+       *--rec_offsets = cpu_to_be16(offset);
+
+       head = (struct hfs_btree_header_rec *)(buf + offset);
+       head->node_size = cpu_to_be16(node_size);
+       tmp = i_size_read(attr_file);
+       do_div(tmp, node_size);
+       head->node_count = cpu_to_be32(tmp);
+       head->free_nodes = cpu_to_be32(be32_to_cpu(head->node_count) - 1);
+       head->clump_size = cpu_to_be32(clump_size);
+       head->attributes |= cpu_to_be32(HFS_TREE_BIGKEYS | HFS_TREE_VARIDXKEYS);
+       head->max_key_len = cpu_to_be16(HFSPLUS_ATTR_KEYLEN - sizeof(u16));
+       offset += sizeof(struct hfs_btree_header_rec);
+       *--rec_offsets = cpu_to_be16(offset);
+       offset += HFSPLUS_BTREE_HDR_USER_BYTES;
+       *--rec_offsets = cpu_to_be16(offset);
+
+       hdr_node_map_rec_bits = 8 * (node_size - offset - (4 * sizeof(u16)));
+       if (be32_to_cpu(head->node_count) > hdr_node_map_rec_bits) {
+               u32 map_node_bits;
+               u32 map_nodes;
+
+               desc->next = cpu_to_be32(be32_to_cpu(head->leaf_tail) + 1);
+               map_node_bits = 8 * (node_size - sizeof(struct hfs_bnode_desc) -
+                                       (2 * sizeof(u16)) - 2);
+               map_nodes = (be32_to_cpu(head->node_count) -
+                               hdr_node_map_rec_bits +
+                               (map_node_bits - 1)) / map_node_bits;
+               be32_add_cpu(&head->free_nodes, 0 - map_nodes);
+       }
+
+       bmp = buf + offset;
+       used_nodes =
+               be32_to_cpu(head->node_count) - be32_to_cpu(head->free_nodes);
+       used_bmp_bytes = used_nodes / 8;
+       if (used_bmp_bytes) {
+               memset(bmp, 0xFF, used_bmp_bytes);
+               bmp += used_bmp_bytes;
+               used_nodes %= 8;
+       }
+       *bmp = ~(0xFF >> used_nodes);
+       offset += hdr_node_map_rec_bits / 8;
+       *--rec_offsets = cpu_to_be16(offset);
+}
+
+static int hfsplus_create_attributes_file(struct super_block *sb)
+{
+       int err = 0;
+       struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
+       struct inode *attr_file;
+       struct hfsplus_inode_info *hip;
+       u32 clump_size;
+       u16 node_size = HFSPLUS_ATTR_TREE_NODE_SIZE;
+       char *buf;
+       int index, written;
+       struct address_space *mapping;
+       struct page *page;
+       int old_state = HFSPLUS_EMPTY_ATTR_TREE;
+
+       hfs_dbg(ATTR_MOD, "create_attr_file: ino %d\n", HFSPLUS_ATTR_CNID);
+
+check_attr_tree_state_again:
+       switch (atomic_read(&sbi->attr_tree_state)) {
+       case HFSPLUS_EMPTY_ATTR_TREE:
+               if (old_state != atomic_cmpxchg(&sbi->attr_tree_state,
+                                               old_state,
+                                               HFSPLUS_CREATING_ATTR_TREE))
+                       goto check_attr_tree_state_again;
+               break;
+       case HFSPLUS_CREATING_ATTR_TREE:
+               /*
+                * This state means that another thread is in process
+                * of AttributesFile creation. Theoretically, it is
+                * possible to be here. But really __setxattr() method
+                * first of all calls hfs_find_init() for lookup in
+                * B-tree of CatalogFile. This method locks mutex of
+                * CatalogFile's B-tree. As a result, if some thread
+                * is inside AttributedFile creation operation then
+                * another threads will be waiting unlocking of
+                * CatalogFile's B-tree's mutex. However, if code will
+                * change then we will return error code (-EAGAIN) from
+                * here. Really, it means that first try to set of xattr
+                * fails with error but second attempt will have success.
+                */
+               return -EAGAIN;
+       case HFSPLUS_VALID_ATTR_TREE:
+               return 0;
+       case HFSPLUS_FAILED_ATTR_TREE:
+               return -EOPNOTSUPP;
+       default:
+               BUG();
+       }
+
+       attr_file = hfsplus_iget(sb, HFSPLUS_ATTR_CNID);
+       if (IS_ERR(attr_file)) {
+               pr_err("failed to load attributes file\n");
+               return PTR_ERR(attr_file);
+       }
+
+       BUG_ON(i_size_read(attr_file) != 0);
+
+       hip = HFSPLUS_I(attr_file);
+
+       clump_size = hfsplus_calc_btree_clump_size(sb->s_blocksize,
+                                                   node_size,
+                                                   sbi->sect_count,
+                                                   HFSPLUS_ATTR_CNID);
+
+       mutex_lock(&hip->extents_lock);
+       hip->clump_blocks = clump_size >> sbi->alloc_blksz_shift;
+       mutex_unlock(&hip->extents_lock);
+
+       if (sbi->free_blocks <= (hip->clump_blocks << 1)) {
+               err = -ENOSPC;
+               goto end_attr_file_creation;
+       }
+
+       while (hip->alloc_blocks < hip->clump_blocks) {
+               err = hfsplus_file_extend(attr_file, false);
+               if (unlikely(err)) {
+                       pr_err("failed to extend attributes file\n");
+                       goto end_attr_file_creation;
+               }
+               hip->phys_size = attr_file->i_size =
+                       (loff_t)hip->alloc_blocks << sbi->alloc_blksz_shift;
+               hip->fs_blocks = hip->alloc_blocks << sbi->fs_shift;
+               inode_set_bytes(attr_file, attr_file->i_size);
+       }
+
+       buf = kzalloc(node_size, GFP_NOFS);
+       if (!buf) {
+               pr_err("failed to allocate memory for header node\n");
+               err = -ENOMEM;
+               goto end_attr_file_creation;
+       }
+
+       hfsplus_init_header_node(attr_file, clump_size, buf, node_size);
+
+       mapping = attr_file->i_mapping;
+
+       index = 0;
+       written = 0;
+       for (; written < node_size; index++, written += PAGE_CACHE_SIZE) {
+               void *kaddr;
+
+               page = read_mapping_page(mapping, index, NULL);
+               if (IS_ERR(page)) {
+                       err = PTR_ERR(page);
+                       goto failed_header_node_init;
+               }
+
+               kaddr = kmap_atomic(page);
+               memcpy(kaddr, buf + written,
+                       min_t(size_t, PAGE_CACHE_SIZE, node_size - written));
+               kunmap_atomic(kaddr);
+
+               set_page_dirty(page);
+               page_cache_release(page);
+       }
+
+       hfsplus_mark_inode_dirty(attr_file, HFSPLUS_I_ATTR_DIRTY);
+
+       sbi->attr_tree = hfs_btree_open(sb, HFSPLUS_ATTR_CNID);
+       if (!sbi->attr_tree)
+               pr_err("failed to load attributes file\n");
+
+failed_header_node_init:
+       kfree(buf);
+
+end_attr_file_creation:
+       iput(attr_file);
+
+       if (!err)
+               atomic_set(&sbi->attr_tree_state, HFSPLUS_VALID_ATTR_TREE);
+       else if (err == -ENOSPC)
+               atomic_set(&sbi->attr_tree_state, HFSPLUS_EMPTY_ATTR_TREE);
+       else
+               atomic_set(&sbi->attr_tree_state, HFSPLUS_FAILED_ATTR_TREE);
+
+       return err;
+}
+
+int __hfsplus_setxattr(struct inode *inode, const char *name,
+                       const void *value, size_t size, int flags)
+{
+       int err = 0;
+       struct hfs_find_data cat_fd;
+       hfsplus_cat_entry entry;
+       u16 cat_entry_flags, cat_entry_type;
+       u16 folder_finderinfo_len = sizeof(struct DInfo) +
+                                       sizeof(struct DXInfo);
+       u16 file_finderinfo_len = sizeof(struct FInfo) +
+                                       sizeof(struct FXInfo);
+
+       if ((!S_ISREG(inode->i_mode) &&
+                       !S_ISDIR(inode->i_mode)) ||
+                               HFSPLUS_IS_RSRC(inode))
+               return -EOPNOTSUPP;
+
+       if (value == NULL)
+               return hfsplus_removexattr(inode, name);
+
+       err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &cat_fd);
+       if (err) {
+               pr_err("can't init xattr find struct\n");
+               return err;
+       }
+
+       err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &cat_fd);
+       if (err) {
+               pr_err("catalog searching failed\n");
+               goto end_setxattr;
+       }
+
+       if (!strcmp_xattr_finder_info(name)) {
+               if (flags & XATTR_CREATE) {
+                       pr_err("xattr exists yet\n");
+                       err = -EOPNOTSUPP;
+                       goto end_setxattr;
+               }
+               hfs_bnode_read(cat_fd.bnode, &entry, cat_fd.entryoffset,
+                                       sizeof(hfsplus_cat_entry));
+               if (be16_to_cpu(entry.type) == HFSPLUS_FOLDER) {
+                       if (size == folder_finderinfo_len) {
+                               memcpy(&entry.folder.user_info, value,
+                                               folder_finderinfo_len);
+                               hfs_bnode_write(cat_fd.bnode, &entry,
+                                       cat_fd.entryoffset,
+                                       sizeof(struct hfsplus_cat_folder));
+                               hfsplus_mark_inode_dirty(inode,
+                                               HFSPLUS_I_CAT_DIRTY);
+                       } else {
+                               err = -ERANGE;
+                               goto end_setxattr;
+                       }
+               } else if (be16_to_cpu(entry.type) == HFSPLUS_FILE) {
+                       if (size == file_finderinfo_len) {
+                               memcpy(&entry.file.user_info, value,
+                                               file_finderinfo_len);
+                               hfs_bnode_write(cat_fd.bnode, &entry,
+                                       cat_fd.entryoffset,
+                                       sizeof(struct hfsplus_cat_file));
+                               hfsplus_mark_inode_dirty(inode,
+                                               HFSPLUS_I_CAT_DIRTY);
+                       } else {
+                               err = -ERANGE;
+                               goto end_setxattr;
+                       }
+               } else {
+                       err = -EOPNOTSUPP;
+                       goto end_setxattr;
+               }
+               goto end_setxattr;
+       }
+
+       if (!HFSPLUS_SB(inode->i_sb)->attr_tree) {
+               err = hfsplus_create_attributes_file(inode->i_sb);
+               if (unlikely(err))
+                       goto end_setxattr;
+       }
+
+       if (hfsplus_attr_exists(inode, name)) {
+               if (flags & XATTR_CREATE) {
+                       pr_err("xattr exists yet\n");
+                       err = -EOPNOTSUPP;
+                       goto end_setxattr;
+               }
+               err = hfsplus_delete_attr(inode, name);
+               if (err)
+                       goto end_setxattr;
+               err = hfsplus_create_attr(inode, name, value, size);
+               if (err)
+                       goto end_setxattr;
+       } else {
+               if (flags & XATTR_REPLACE) {
+                       pr_err("cannot replace xattr\n");
+                       err = -EOPNOTSUPP;
+                       goto end_setxattr;
+               }
+               err = hfsplus_create_attr(inode, name, value, size);
+               if (err)
+                       goto end_setxattr;
+       }
+
+       cat_entry_type = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset);
+       if (cat_entry_type == HFSPLUS_FOLDER) {
+               cat_entry_flags = hfs_bnode_read_u16(cat_fd.bnode,
+                                   cat_fd.entryoffset +
+                                   offsetof(struct hfsplus_cat_folder, flags));
+               cat_entry_flags |= HFSPLUS_XATTR_EXISTS;
+               if (!strcmp_xattr_acl(name))
+                       cat_entry_flags |= HFSPLUS_ACL_EXISTS;
+               hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
+                               offsetof(struct hfsplus_cat_folder, flags),
+                               cat_entry_flags);
+               hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
+       } else if (cat_entry_type == HFSPLUS_FILE) {
+               cat_entry_flags = hfs_bnode_read_u16(cat_fd.bnode,
+                                   cat_fd.entryoffset +
+                                   offsetof(struct hfsplus_cat_file, flags));
+               cat_entry_flags |= HFSPLUS_XATTR_EXISTS;
+               if (!strcmp_xattr_acl(name))
+                       cat_entry_flags |= HFSPLUS_ACL_EXISTS;
+               hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
+                                   offsetof(struct hfsplus_cat_file, flags),
+                                   cat_entry_flags);
+               hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
+       } else {
+               pr_err("invalid catalog entry type\n");
+               err = -EIO;
+               goto end_setxattr;
+       }
+
+end_setxattr:
+       hfs_find_exit(&cat_fd);
+       return err;
+}
+
+static int name_len(const char *xattr_name, int xattr_name_len)
+{
+       int len = xattr_name_len + 1;
+
+       if (!is_known_namespace(xattr_name))
+               len += XATTR_MAC_OSX_PREFIX_LEN;
+
+       return len;
+}
+
+static int copy_name(char *buffer, const char *xattr_name, int name_len)
+{
+       int len = name_len;
+       int offset = 0;
+
+       if (!is_known_namespace(xattr_name)) {
+               strncpy(buffer, XATTR_MAC_OSX_PREFIX, XATTR_MAC_OSX_PREFIX_LEN);
+               offset += XATTR_MAC_OSX_PREFIX_LEN;
+               len += XATTR_MAC_OSX_PREFIX_LEN;
+       }
+
+       strncpy(buffer + offset, xattr_name, name_len);
+       memset(buffer + offset + name_len, 0, 1);
+       len += 1;
+
+       return len;
+}
+
+int hfsplus_setxattr(struct dentry *dentry, const char *name,
+                    const void *value, size_t size, int flags,
+                    const char *prefix, size_t prefixlen)
+{
+       char *xattr_name;
+       int res;
+
+       if (!strcmp(name, ""))
+               return -EINVAL;
+
+       xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
+               GFP_KERNEL);
+       if (!xattr_name)
+               return -ENOMEM;
+       strcpy(xattr_name, prefix);
+       strcpy(xattr_name + prefixlen, name);
+       res = __hfsplus_setxattr(d_inode(dentry), xattr_name, value, size,
+                                flags);
+       kfree(xattr_name);
+       return res;
+}
+
+static ssize_t hfsplus_getxattr_finder_info(struct inode *inode,
+                                               void *value, size_t size)
+{
+       ssize_t res = 0;
+       struct hfs_find_data fd;
+       u16 entry_type;
+       u16 folder_rec_len = sizeof(struct DInfo) + sizeof(struct DXInfo);
+       u16 file_rec_len = sizeof(struct FInfo) + sizeof(struct FXInfo);
+       u16 record_len = max(folder_rec_len, file_rec_len);
+       u8 folder_finder_info[sizeof(struct DInfo) + sizeof(struct DXInfo)];
+       u8 file_finder_info[sizeof(struct FInfo) + sizeof(struct FXInfo)];
+
+       if (size >= record_len) {
+               res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
+               if (res) {
+                       pr_err("can't init xattr find struct\n");
+                       return res;
+               }
+               res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
+               if (res)
+                       goto end_getxattr_finder_info;
+               entry_type = hfs_bnode_read_u16(fd.bnode, fd.entryoffset);
+
+               if (entry_type == HFSPLUS_FOLDER) {
+                       hfs_bnode_read(fd.bnode, folder_finder_info,
+                               fd.entryoffset +
+                               offsetof(struct hfsplus_cat_folder, user_info),
+                               folder_rec_len);
+                       memcpy(value, folder_finder_info, folder_rec_len);
+                       res = folder_rec_len;
+               } else if (entry_type == HFSPLUS_FILE) {
+                       hfs_bnode_read(fd.bnode, file_finder_info,
+                               fd.entryoffset +
+                               offsetof(struct hfsplus_cat_file, user_info),
+                               file_rec_len);
+                       memcpy(value, file_finder_info, file_rec_len);
+                       res = file_rec_len;
+               } else {
+                       res = -EOPNOTSUPP;
+                       goto end_getxattr_finder_info;
+               }
+       } else
+               res = size ? -ERANGE : record_len;
+
+end_getxattr_finder_info:
+       if (size >= record_len)
+               hfs_find_exit(&fd);
+       return res;
+}
+
+ssize_t __hfsplus_getxattr(struct inode *inode, const char *name,
+                        void *value, size_t size)
+{
+       struct hfs_find_data fd;
+       hfsplus_attr_entry *entry;
+       __be32 xattr_record_type;
+       u32 record_type;
+       u16 record_length = 0;
+       ssize_t res = 0;
+
+       if ((!S_ISREG(inode->i_mode) &&
+                       !S_ISDIR(inode->i_mode)) ||
+                               HFSPLUS_IS_RSRC(inode))
+               return -EOPNOTSUPP;
+
+       if (!strcmp_xattr_finder_info(name))
+               return hfsplus_getxattr_finder_info(inode, value, size);
+
+       if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
+               return -EOPNOTSUPP;
+
+       entry = hfsplus_alloc_attr_entry();
+       if (!entry) {
+               pr_err("can't allocate xattr entry\n");
+               return -ENOMEM;
+       }
+
+       res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->attr_tree, &fd);
+       if (res) {
+               pr_err("can't init xattr find struct\n");
+               goto failed_getxattr_init;
+       }
+
+       res = hfsplus_find_attr(inode->i_sb, inode->i_ino, name, &fd);
+       if (res) {
+               if (res == -ENOENT)
+                       res = -ENODATA;
+               else
+                       pr_err("xattr searching failed\n");
+               goto out;
+       }
+
+       hfs_bnode_read(fd.bnode, &xattr_record_type,
+                       fd.entryoffset, sizeof(xattr_record_type));
+       record_type = be32_to_cpu(xattr_record_type);
+       if (record_type == HFSPLUS_ATTR_INLINE_DATA) {
+               record_length = hfs_bnode_read_u16(fd.bnode,
+                               fd.entryoffset +
+                               offsetof(struct hfsplus_attr_inline_data,
+                               length));
+               if (record_length > HFSPLUS_MAX_INLINE_DATA_SIZE) {
+                       pr_err("invalid xattr record size\n");
+                       res = -EIO;
+                       goto out;
+               }
+       } else if (record_type == HFSPLUS_ATTR_FORK_DATA ||
+                       record_type == HFSPLUS_ATTR_EXTENTS) {
+               pr_err("only inline data xattr are supported\n");
+               res = -EOPNOTSUPP;
+               goto out;
+       } else {
+               pr_err("invalid xattr record\n");
+               res = -EIO;
+               goto out;
+       }
+
+       if (size) {
+               hfs_bnode_read(fd.bnode, entry, fd.entryoffset,
+                               offsetof(struct hfsplus_attr_inline_data,
+                                       raw_bytes) + record_length);
+       }
+
+       if (size >= record_length) {
+               memcpy(value, entry->inline_data.raw_bytes, record_length);
+               res = record_length;
+       } else
+               res = size ? -ERANGE : record_length;
+
+out:
+       hfs_find_exit(&fd);
+
+failed_getxattr_init:
+       hfsplus_destroy_attr_entry(entry);
+       return res;
+}
+
+ssize_t hfsplus_getxattr(struct dentry *dentry, const char *name,
+                        void *value, size_t size,
+                        const char *prefix, size_t prefixlen)
+{
+       int res;
+       char *xattr_name;
+
+       if (!strcmp(name, ""))
+               return -EINVAL;
+
+       xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
+                            GFP_KERNEL);
+       if (!xattr_name)
+               return -ENOMEM;
+
+       strcpy(xattr_name, prefix);
+       strcpy(xattr_name + prefixlen, name);
+
+       res = __hfsplus_getxattr(d_inode(dentry), xattr_name, value, size);
+       kfree(xattr_name);
+       return res;
+
+}
+
+static inline int can_list(const char *xattr_name)
+{
+       if (!xattr_name)
+               return 0;
+
+       return strncmp(xattr_name, XATTR_TRUSTED_PREFIX,
+                       XATTR_TRUSTED_PREFIX_LEN) ||
+                               capable(CAP_SYS_ADMIN);
+}
+
+static ssize_t hfsplus_listxattr_finder_info(struct dentry *dentry,
+                                               char *buffer, size_t size)
+{
+       ssize_t res = 0;
+       struct inode *inode = d_inode(dentry);
+       struct hfs_find_data fd;
+       u16 entry_type;
+       u8 folder_finder_info[sizeof(struct DInfo) + sizeof(struct DXInfo)];
+       u8 file_finder_info[sizeof(struct FInfo) + sizeof(struct FXInfo)];
+       unsigned long len, found_bit;
+       int xattr_name_len, symbols_count;
+
+       res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
+       if (res) {
+               pr_err("can't init xattr find struct\n");
+               return res;
+       }
+
+       res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
+       if (res)
+               goto end_listxattr_finder_info;
+
+       entry_type = hfs_bnode_read_u16(fd.bnode, fd.entryoffset);
+       if (entry_type == HFSPLUS_FOLDER) {
+               len = sizeof(struct DInfo) + sizeof(struct DXInfo);
+               hfs_bnode_read(fd.bnode, folder_finder_info,
+                               fd.entryoffset +
+                               offsetof(struct hfsplus_cat_folder, user_info),
+                               len);
+               found_bit = find_first_bit((void *)folder_finder_info, len*8);
+       } else if (entry_type == HFSPLUS_FILE) {
+               len = sizeof(struct FInfo) + sizeof(struct FXInfo);
+               hfs_bnode_read(fd.bnode, file_finder_info,
+                               fd.entryoffset +
+                               offsetof(struct hfsplus_cat_file, user_info),
+                               len);
+               found_bit = find_first_bit((void *)file_finder_info, len*8);
+       } else {
+               res = -EOPNOTSUPP;
+               goto end_listxattr_finder_info;
+       }
+
+       if (found_bit >= (len*8))
+               res = 0;
+       else {
+               symbols_count = sizeof(HFSPLUS_XATTR_FINDER_INFO_NAME) - 1;
+               xattr_name_len =
+                       name_len(HFSPLUS_XATTR_FINDER_INFO_NAME, symbols_count);
+               if (!buffer || !size) {
+                       if (can_list(HFSPLUS_XATTR_FINDER_INFO_NAME))
+                               res = xattr_name_len;
+               } else if (can_list(HFSPLUS_XATTR_FINDER_INFO_NAME)) {
+                       if (size < xattr_name_len)
+                               res = -ERANGE;
+                       else {
+                               res = copy_name(buffer,
+                                               HFSPLUS_XATTR_FINDER_INFO_NAME,
+                                               symbols_count);
+                       }
+               }
+       }
+
+end_listxattr_finder_info:
+       hfs_find_exit(&fd);
+
+       return res;
+}
+
+ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
+{
+       ssize_t err;
+       ssize_t res = 0;
+       struct inode *inode = d_inode(dentry);
+       struct hfs_find_data fd;
+       u16 key_len = 0;
+       struct hfsplus_attr_key attr_key;
+       char *strbuf;
+       int xattr_name_len;
+
+       if ((!S_ISREG(inode->i_mode) &&
+                       !S_ISDIR(inode->i_mode)) ||
+                               HFSPLUS_IS_RSRC(inode))
+               return -EOPNOTSUPP;
+
+       res = hfsplus_listxattr_finder_info(dentry, buffer, size);
+       if (res < 0)
+               return res;
+       else if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
+               return (res == 0) ? -EOPNOTSUPP : res;
+
+       err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->attr_tree, &fd);
+       if (err) {
+               pr_err("can't init xattr find struct\n");
+               return err;
+       }
+
+       strbuf = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN +
+                       XATTR_MAC_OSX_PREFIX_LEN + 1, GFP_KERNEL);
+       if (!strbuf) {
+               res = -ENOMEM;
+               goto out;
+       }
+
+       err = hfsplus_find_attr(inode->i_sb, inode->i_ino, NULL, &fd);
+       if (err) {
+               if (err == -ENOENT) {
+                       if (res == 0)
+                               res = -ENODATA;
+                       goto end_listxattr;
+               } else {
+                       res = err;
+                       goto end_listxattr;
+               }
+       }
+
+       for (;;) {
+               key_len = hfs_bnode_read_u16(fd.bnode, fd.keyoffset);
+               if (key_len == 0 || key_len > fd.tree->max_key_len) {
+                       pr_err("invalid xattr key length: %d\n", key_len);
+                       res = -EIO;
+                       goto end_listxattr;
+               }
+
+               hfs_bnode_read(fd.bnode, &attr_key,
+                               fd.keyoffset, key_len + sizeof(key_len));
+
+               if (be32_to_cpu(attr_key.cnid) != inode->i_ino)
+                       goto end_listxattr;
+
+               xattr_name_len = NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN;
+               if (hfsplus_uni2asc(inode->i_sb,
+                       (const struct hfsplus_unistr *)&fd.key->attr.key_name,
+                                       strbuf, &xattr_name_len)) {
+                       pr_err("unicode conversion failed\n");
+                       res = -EIO;
+                       goto end_listxattr;
+               }
+
+               if (!buffer || !size) {
+                       if (can_list(strbuf))
+                               res += name_len(strbuf, xattr_name_len);
+               } else if (can_list(strbuf)) {
+                       if (size < (res + name_len(strbuf, xattr_name_len))) {
+                               res = -ERANGE;
+                               goto end_listxattr;
+                       } else
+                               res += copy_name(buffer + res,
+                                               strbuf, xattr_name_len);
+               }
+
+               if (hfs_brec_goto(&fd, 1))
+                       goto end_listxattr;
+       }
+
+end_listxattr:
+       kfree(strbuf);
+out:
+       hfs_find_exit(&fd);
+       return res;
+}
+
+static int hfsplus_removexattr(struct inode *inode, const char *name)
+{
+       int err = 0;
+       struct hfs_find_data cat_fd;
+       u16 flags;
+       u16 cat_entry_type;
+       int is_xattr_acl_deleted = 0;
+       int is_all_xattrs_deleted = 0;
+
+       if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
+               return -EOPNOTSUPP;
+
+       if (!strcmp_xattr_finder_info(name))
+               return -EOPNOTSUPP;
+
+       err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &cat_fd);
+       if (err) {
+               pr_err("can't init xattr find struct\n");
+               return err;
+       }
+
+       err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &cat_fd);
+       if (err) {
+               pr_err("catalog searching failed\n");
+               goto end_removexattr;
+       }
+
+       err = hfsplus_delete_attr(inode, name);
+       if (err)
+               goto end_removexattr;
+
+       is_xattr_acl_deleted = !strcmp_xattr_acl(name);
+       is_all_xattrs_deleted = !hfsplus_attr_exists(inode, NULL);
+
+       if (!is_xattr_acl_deleted && !is_all_xattrs_deleted)
+               goto end_removexattr;
+
+       cat_entry_type = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset);
+
+       if (cat_entry_type == HFSPLUS_FOLDER) {
+               flags = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset +
+                               offsetof(struct hfsplus_cat_folder, flags));
+               if (is_xattr_acl_deleted)
+                       flags &= ~HFSPLUS_ACL_EXISTS;
+               if (is_all_xattrs_deleted)
+                       flags &= ~HFSPLUS_XATTR_EXISTS;
+               hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
+                               offsetof(struct hfsplus_cat_folder, flags),
+                               flags);
+               hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
+       } else if (cat_entry_type == HFSPLUS_FILE) {
+               flags = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset +
+                               offsetof(struct hfsplus_cat_file, flags));
+               if (is_xattr_acl_deleted)
+                       flags &= ~HFSPLUS_ACL_EXISTS;
+               if (is_all_xattrs_deleted)
+                       flags &= ~HFSPLUS_XATTR_EXISTS;
+               hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
+                               offsetof(struct hfsplus_cat_file, flags),
+                               flags);
+               hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
+       } else {
+               pr_err("invalid catalog entry type\n");
+               err = -EIO;
+               goto end_removexattr;
+       }
+
+end_removexattr:
+       hfs_find_exit(&cat_fd);
+       return err;
+}
+
+static int hfsplus_osx_getxattr(struct dentry *dentry, const char *name,
+                                       void *buffer, size_t size, int type)
+{
+       if (!strcmp(name, ""))
+               return -EINVAL;
+
+       /*
+        * Don't allow retrieving properly prefixed attributes
+        * by prepending them with "osx."
+        */
+       if (is_known_namespace(name))
+               return -EOPNOTSUPP;
+
+       /*
+        * osx is the namespace we use to indicate an unprefixed
+        * attribute on the filesystem (like the ones that OS X
+        * creates), so we pass the name through unmodified (after
+        * ensuring it doesn't conflict with another namespace).
+        */
+       return __hfsplus_getxattr(d_inode(dentry), name, buffer, size);
+}
+
+static int hfsplus_osx_setxattr(struct dentry *dentry, const char *name,
+               const void *buffer, size_t size, int flags, int type)
+{
+       if (!strcmp(name, ""))
+               return -EINVAL;
+
+       /*
+        * Don't allow setting properly prefixed attributes
+        * by prepending them with "osx."
+        */
+       if (is_known_namespace(name))
+               return -EOPNOTSUPP;
+
+       /*
+        * osx is the namespace we use to indicate an unprefixed
+        * attribute on the filesystem (like the ones that OS X
+        * creates), so we pass the name through unmodified (after
+        * ensuring it doesn't conflict with another namespace).
+        */
+       return __hfsplus_setxattr(d_inode(dentry), name, buffer, size, flags);
+}
+
+static size_t hfsplus_osx_listxattr(struct dentry *dentry, char *list,
+               size_t list_size, const char *name, size_t name_len, int type)
+{
+       /*
+        * This method is not used.
+        * It is used hfsplus_listxattr() instead of generic_listxattr().
+        */
+       return -EOPNOTSUPP;
+}
+
+const struct xattr_handler hfsplus_xattr_osx_handler = {
+       .prefix = XATTR_MAC_OSX_PREFIX,
+       .list   = hfsplus_osx_listxattr,
+       .get    = hfsplus_osx_getxattr,
+       .set    = hfsplus_osx_setxattr,
+};