From 5103e947b9b7ac18ddb21a04ee3486e94c6504d7 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Fri, 16 Nov 2007 11:45:54 -0500 Subject: [PATCH] xattr support for btrfs Signed-off-by: Chris Mason --- fs/btrfs/Makefile | 2 +- fs/btrfs/acl.c | 66 +++++++ fs/btrfs/ctree.h | 22 ++- fs/btrfs/dir-item.c | 100 +++++++++- fs/btrfs/inode.c | 15 +- fs/btrfs/print-tree.c | 3 +- fs/btrfs/super.c | 2 + fs/btrfs/xattr.c | 497 ++++++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/xattr.h | 58 ++++++ 9 files changed, 751 insertions(+), 14 deletions(-) create mode 100644 fs/btrfs/acl.c create mode 100644 fs/btrfs/xattr.c create mode 100644 fs/btrfs/xattr.h diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile index 551743b..d5804c5 100644 --- a/fs/btrfs/Makefile +++ b/fs/btrfs/Makefile @@ -5,7 +5,7 @@ obj-m := btrfs.o btrfs-y := super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \ hash.o file-item.o inode-item.o inode-map.o disk-io.o \ transaction.o bit-radix.o inode.o file.o tree-defrag.o \ - extent_map.o sysfs.o struct-funcs.o + extent_map.o sysfs.o struct-funcs.o xattr.o acl.o #btrfs-y := ctree.o disk-io.o radix-tree.o extent-tree.o print-tree.o \ # root-tree.o dir-item.o hash.o file-item.o inode-item.o \ diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c new file mode 100644 index 0000000..aee9f06 --- /dev/null +++ b/fs/btrfs/acl.c @@ -0,0 +1,66 @@ +/* + * Copyright (C) 2007 Red Hat. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * 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, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include +#include +#include +#include +#include "ctree.h" +#include "xattr.h" + +static int btrfs_xattr_acl_access_get(struct inode *inode, const char *name, + void *value, size_t size) +{ + return btrfs_xattr_get(inode, BTRFS_XATTR_INDEX_POSIX_ACL_ACCESS, name, + value, size); +} + +static int btrfs_xattr_acl_access_set(struct inode *inode, const char *name, + const void *value, size_t size, int flags) +{ + return btrfs_xattr_set(inode, BTRFS_XATTR_INDEX_POSIX_ACL_ACCESS, name, + value, size, flags); +} + +static int btrfs_xattr_acl_default_get(struct inode *inode, const char *name, + void *value, size_t size) +{ + return btrfs_xattr_get(inode, BTRFS_XATTR_INDEX_POSIX_ACL_DEFAULT, + name, value, size); +} + +static int btrfs_xattr_acl_default_set(struct inode *inode, const char *name, + const void *value, size_t size, int flags) +{ + return btrfs_xattr_set(inode, BTRFS_XATTR_INDEX_POSIX_ACL_DEFAULT, + name, value, size, flags); +} + +struct xattr_handler btrfs_xattr_acl_default_handler = { + .prefix = POSIX_ACL_XATTR_DEFAULT, + .list = btrfs_xattr_generic_list, + .get = btrfs_xattr_acl_default_get, + .set = btrfs_xattr_acl_default_set, +}; + +struct xattr_handler btrfs_xattr_acl_access_handler = { + .prefix = POSIX_ACL_XATTR_ACCESS, + .list = btrfs_xattr_generic_list, + .get = btrfs_xattr_acl_access_get, + .set = btrfs_xattr_acl_access_set, +}; diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 030d21d..27cadae 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -63,7 +63,8 @@ extern struct kmem_cache *btrfs_path_cachep; #define BTRFS_FT_FIFO 5 #define BTRFS_FT_SOCK 6 #define BTRFS_FT_SYMLINK 7 -#define BTRFS_FT_MAX 8 +#define BTRFS_FT_XATTR 8 +#define BTRFS_FT_MAX 9 /* * the key defines the order in the tree, and so it also defines (optimal) @@ -226,7 +227,7 @@ struct btrfs_inode_item { struct btrfs_dir_item { struct btrfs_disk_key location; - __le16 flags; + __le16 data_len; __le16 name_len; u8 type; } __attribute__ ((__packed__)); @@ -367,7 +368,7 @@ struct btrfs_root { * the FS */ #define BTRFS_INODE_ITEM_KEY 1 - +#define BTRFS_XATTR_ITEM_KEY 2 /* reserve 2-15 close to the inode for later flexibility */ /* @@ -621,7 +622,7 @@ static inline void btrfs_set_item_key(struct extent_buffer *eb, } /* struct btrfs_dir_item */ -BTRFS_SETGET_FUNCS(dir_flags, struct btrfs_dir_item, flags, 16); +BTRFS_SETGET_FUNCS(dir_data_len, struct btrfs_dir_item, data_len, 16); BTRFS_SETGET_FUNCS(dir_type, struct btrfs_dir_item, type, 8); BTRFS_SETGET_FUNCS(dir_name_len, struct btrfs_dir_item, name_len, 16); @@ -962,6 +963,15 @@ int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, struct btrfs_dir_item *di); +int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, const char *name, + u16 name_len, const void *data, u16 data_len, + u64 dir); +struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, u64 dir, + const char *name, u16 name_len, + int mod); /* inode-map.c */ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans, struct btrfs_root *fs_root, @@ -1039,4 +1049,8 @@ int btrfs_sysfs_add_root(struct btrfs_root *root); void btrfs_sysfs_del_root(struct btrfs_root *root); void btrfs_sysfs_del_super(struct btrfs_fs_info *root); +/* xattr.c */ +ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size); +int btrfs_delete_xattrs(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct inode *inode); #endif diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c index 514a1dc..ddbe12a 100644 --- a/fs/btrfs/dir-item.c +++ b/fs/btrfs/dir-item.c @@ -43,8 +43,6 @@ static struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle return ERR_PTR(-EEXIST); ret = btrfs_extend_item(trans, root, path, data_size); WARN_ON(ret > 0); - if (ret) - return ERR_PTR(ret); } if (ret < 0) return ERR_PTR(ret); @@ -57,6 +55,57 @@ static struct btrfs_dir_item *insert_with_overflow(struct btrfs_trans_handle return (struct btrfs_dir_item *)ptr; } +int btrfs_insert_xattr_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, const char *name, + u16 name_len, const void *data, u16 data_len, + u64 dir) +{ + int ret = 0; + struct btrfs_path *path; + struct btrfs_dir_item *dir_item; + unsigned long name_ptr, data_ptr; + struct btrfs_key key, location; + struct btrfs_disk_key disk_key; + struct extent_buffer *leaf; + u32 data_size; + + key.objectid = dir; + btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY); + ret = btrfs_name_hash(name, name_len, &key.offset); + BUG_ON(ret); + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + data_size = sizeof(*dir_item) + name_len + data_len; + dir_item = insert_with_overflow(trans, root, path, &key, data_size, + name, name_len); + /* + * FIXME: at some point we should handle xattr's that are larger than + * what we can fit in our leaf. We set location to NULL b/c we arent + * pointing at anything else, that will change if we store the xattr + * data in a separate inode. + */ + BUG_ON(IS_ERR(dir_item)); + memset(&location, 0, sizeof(location)); + + leaf = path->nodes[0]; + btrfs_cpu_key_to_disk(&disk_key, &location); + btrfs_set_dir_item_key(leaf, dir_item, &disk_key); + btrfs_set_dir_type(leaf, dir_item, BTRFS_FT_XATTR); + btrfs_set_dir_name_len(leaf, dir_item, name_len); + btrfs_set_dir_data_len(leaf, dir_item, data_len); + name_ptr = (unsigned long)(dir_item + 1); + data_ptr = (unsigned long)((char *)name_ptr + name_len); + + write_extent_buffer(leaf, name, name_ptr, name_len); + write_extent_buffer(leaf, data, data_ptr, data_len); + btrfs_mark_buffer_dirty(path->nodes[0]); + + btrfs_free_path(path); + return ret; +} + int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, const char *name, int name_len, u64 dir, struct btrfs_key *location, u8 type) @@ -90,7 +139,7 @@ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root btrfs_cpu_key_to_disk(&disk_key, location); btrfs_set_dir_item_key(leaf, dir_item, &disk_key); btrfs_set_dir_type(leaf, dir_item, type); - btrfs_set_dir_flags(leaf, dir_item, 0); + btrfs_set_dir_data_len(leaf, dir_item, 0); btrfs_set_dir_name_len(leaf, dir_item, name_len); name_ptr = (unsigned long)(dir_item + 1); @@ -117,7 +166,7 @@ second_insert: btrfs_cpu_key_to_disk(&disk_key, location); btrfs_set_dir_item_key(leaf, dir_item, &disk_key); btrfs_set_dir_type(leaf, dir_item, type); - btrfs_set_dir_flags(leaf, dir_item, 0); + btrfs_set_dir_data_len(leaf, dir_item, 0); btrfs_set_dir_name_len(leaf, dir_item, name_len); name_ptr = (unsigned long)(dir_item + 1); write_extent_buffer(leaf, name, name_ptr, name_len); @@ -194,6 +243,43 @@ btrfs_lookup_dir_index_item(struct btrfs_trans_handle *trans, return btrfs_match_dir_item_name(root, path, name, name_len); } +struct btrfs_dir_item *btrfs_lookup_xattr(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, u64 dir, + const char *name, u16 name_len, + int mod) +{ + int ret; + struct btrfs_key key; + int ins_len = mod < 0 ? -1 : 0; + int cow = mod != 0; + struct btrfs_key found_key; + struct extent_buffer *leaf; + + key.objectid = dir; + btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY); + ret = btrfs_name_hash(name, name_len, &key.offset); + BUG_ON(ret); + ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow); + if (ret < 0) + return ERR_PTR(ret); + if (ret > 0) { + if (path->slots[0] == 0) + return NULL; + path->slots[0]--; + } + + leaf = path->nodes[0]; + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + + if (found_key.objectid != dir || + btrfs_key_type(&found_key) != BTRFS_XATTR_ITEM_KEY || + found_key.offset != key.offset) + return NULL; + + return btrfs_match_dir_item_name(root, path, name, name_len); +} + struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root, struct btrfs_path *path, const char *name, int name_len) @@ -210,7 +296,8 @@ struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root, total_len = btrfs_item_size_nr(leaf, path->slots[0]); while(cur < total_len) { this_len = sizeof(*dir_item) + - btrfs_dir_name_len(leaf, dir_item); + btrfs_dir_name_len(leaf, dir_item) + + btrfs_dir_data_len(leaf, dir_item); name_ptr = (unsigned long)(dir_item + 1); if (btrfs_dir_name_len(leaf, dir_item) == name_len && @@ -236,7 +323,8 @@ int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans, int ret = 0; leaf = path->nodes[0]; - sub_item_len = sizeof(*di) + btrfs_dir_name_len(leaf, di); + sub_item_len = sizeof(*di) + btrfs_dir_name_len(leaf, di) + + btrfs_dir_data_len(leaf, di); item_len = btrfs_item_size_nr(leaf, path->slots[0]); if (sub_item_len == item_len) { ret = btrfs_del_item(trans, root, path); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index d6d3246..37f8e03 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -32,6 +32,7 @@ #include #include #include +#include #include "ctree.h" #include "disk-io.h" #include "transaction.h" @@ -841,6 +842,9 @@ void btrfs_delete_inode(struct inode *inode) ret = btrfs_truncate_in_trans(trans, root, inode); if (ret) goto no_delete_lock; + ret = btrfs_delete_xattrs(trans, root, inode); + if (ret) + goto no_delete_lock; ret = btrfs_free_inode(trans, root, inode); if (ret) goto no_delete_lock; @@ -1110,7 +1114,8 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir) if (over) goto nopos; - di_len = btrfs_dir_name_len(leaf, di) + sizeof(*di); + di_len = btrfs_dir_name_len(leaf, di) + + btrfs_dir_data_len(leaf, di) +sizeof(*di); di_cur += di_len; di = (struct btrfs_dir_item *)((char *)di + di_len); } @@ -2519,6 +2524,10 @@ static struct inode_operations btrfs_dir_inode_operations = { .symlink = btrfs_symlink, .setattr = btrfs_setattr, .mknod = btrfs_mknod, + .setxattr = generic_setxattr, + .getxattr = generic_getxattr, + .listxattr = btrfs_listxattr, + .removexattr = generic_removexattr, }; static struct inode_operations btrfs_dir_ro_inode_operations = { @@ -2567,6 +2576,10 @@ static struct inode_operations btrfs_file_inode_operations = { .truncate = btrfs_truncate, .getattr = btrfs_getattr, .setattr = btrfs_setattr, + .setxattr = generic_setxattr, + .getxattr = generic_getxattr, + .listxattr = btrfs_listxattr, + .removexattr = generic_removexattr, }; static struct inode_operations btrfs_special_inode_operations = { diff --git a/fs/btrfs/print-tree.c b/fs/btrfs/print-tree.c index 9f8696c..030324f 100644 --- a/fs/btrfs/print-tree.c +++ b/fs/btrfs/print-tree.c @@ -58,9 +58,8 @@ void btrfs_print_leaf(struct btrfs_root *root, struct extent_buffer *l) case BTRFS_DIR_ITEM_KEY: di = btrfs_item_ptr(l, i, struct btrfs_dir_item); btrfs_dir_item_key_to_cpu(l, di, &found_key); - printk("\t\tdir oid %llu flags %u type %u\n", + printk("\t\tdir oid %llu type %u\n", (unsigned long long)found_key.objectid, - btrfs_dir_flags(l, di), btrfs_dir_type(l, di)); break; case BTRFS_ROOT_ITEM_KEY: diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index f94aa1f..c46bc39 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -40,6 +40,7 @@ #include "btrfs_inode.h" #include "ioctl.h" #include "print-tree.h" +#include "xattr.h" #define BTRFS_SUPER_MAGIC 0x9123683E @@ -106,6 +107,7 @@ static int btrfs_fill_super(struct super_block * sb, void * data, int silent) sb->s_maxbytes = MAX_LFS_FILESIZE; sb->s_magic = BTRFS_SUPER_MAGIC; sb->s_op = &btrfs_super_ops; + sb->s_xattr = btrfs_xattr_handlers; sb->s_time_gran = 1; tree_root = open_ctree(sb); diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c new file mode 100644 index 0000000..f4ac5e0 --- /dev/null +++ b/fs/btrfs/xattr.c @@ -0,0 +1,497 @@ +/* + * Copyright (C) 2007 Red Hat. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * 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, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include +#include +#include +#include +#include +#include "ctree.h" +#include "btrfs_inode.h" +#include "transaction.h" +#include "xattr.h" +#include "disk-io.h" + +static struct xattr_handler *btrfs_xattr_handler_map[] = { + [BTRFS_XATTR_INDEX_USER] = &btrfs_xattr_user_handler, + [BTRFS_XATTR_INDEX_POSIX_ACL_ACCESS] = &btrfs_xattr_acl_access_handler, + [BTRFS_XATTR_INDEX_POSIX_ACL_DEFAULT] = &btrfs_xattr_acl_default_handler, + [BTRFS_XATTR_INDEX_TRUSTED] = &btrfs_xattr_trusted_handler, + [BTRFS_XATTR_INDEX_SECURITY] = &btrfs_xattr_security_handler, + [BTRFS_XATTR_INDEX_SYSTEM] = &btrfs_xattr_system_handler, +}; + +struct xattr_handler *btrfs_xattr_handlers[] = { + &btrfs_xattr_user_handler, + &btrfs_xattr_acl_access_handler, + &btrfs_xattr_acl_default_handler, + &btrfs_xattr_trusted_handler, + &btrfs_xattr_security_handler, + &btrfs_xattr_system_handler, + NULL, +}; + +/* + * @param name - the xattr name + * @return - the xattr_handler for the xattr, NULL if its not found + * + * use this with listxattr where we don't already know the type of xattr we + * have + */ +static struct xattr_handler *find_btrfs_xattr_handler(struct extent_buffer *l, + unsigned long name_ptr, + u16 name_len) +{ + struct xattr_handler *handler = NULL; + int i = 0; + + for (handler = btrfs_xattr_handlers[i]; handler != NULL; i++, + handler = btrfs_xattr_handlers[i]) { + u16 prefix_len = strlen(handler->prefix); + + if (name_len < prefix_len) + continue; + + if (memcmp_extent_buffer(l, handler->prefix, name_ptr, + prefix_len) == 0) + break; + } + + return handler; +} + +/* + * @param name_index - the index for the xattr handler + * @return the xattr_handler if we found it, NULL otherwise + * + * use this if we know the type of the xattr already + */ +static struct xattr_handler *btrfs_xattr_handler(int name_index) +{ + struct xattr_handler *handler = NULL; + + if (name_index >= 0 && + name_index < ARRAY_SIZE(btrfs_xattr_handler_map)) + handler = btrfs_xattr_handler_map[name_index]; + + return handler; +} + +static inline char *get_name(const char *name, int name_index) +{ + char *ret = NULL; + struct xattr_handler *handler = btrfs_xattr_handler(name_index); + int prefix_len; + + if (!handler) + return ret; + + prefix_len = strlen(handler->prefix); + + ret = kmalloc(strlen(name) + prefix_len + 1, GFP_KERNEL); + if (!ret) + return ret; + + memcpy(ret, handler->prefix, prefix_len); + memcpy(ret+prefix_len, name, strlen(name)); + ret[prefix_len + strlen(name)] = '\0'; + + return ret; +} + +size_t btrfs_xattr_generic_list(struct inode *inode, char *list, + size_t list_size, const char *name, + size_t name_len) +{ + if (list && (name_len+1) <= list_size) { + memcpy(list, name, name_len); + list[name_len] = '\0'; + } else + return -ERANGE; + + return name_len+1; +} + +ssize_t btrfs_xattr_get(struct inode *inode, int name_index, + const char *attr_name, void *buffer, size_t size) +{ + struct btrfs_dir_item *di; + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_path *path; + struct extent_buffer *leaf; + struct xattr_handler *handler = btrfs_xattr_handler(name_index); + int ret = 0; + unsigned long data_ptr; + char *name; + + if (!handler) + return -EOPNOTSUPP; + + /* just in case... */ + if (*attr_name == '\0') + return -EINVAL; + + name = get_name(attr_name, name_index); + if (!name) + return -ENOMEM; + + path = btrfs_alloc_path(); + if (!path) { + kfree(name); + return -ENOMEM; + } + + mutex_lock(&root->fs_info->fs_mutex); + /* lookup the xattr by name */ + di = btrfs_lookup_xattr(NULL, root, path, inode->i_ino, name, + strlen(name), 0); + if (!di || IS_ERR(di)) { + ret = -ENODATA; + goto out; + } + + leaf = path->nodes[0]; + /* if size is 0, that means we want the size of the attr */ + if (!size) { + ret = btrfs_dir_data_len(leaf, di); + goto out; + } + + /* now get the data out of our dir_item */ + if (btrfs_dir_data_len(leaf, di) > size) { + ret = -ERANGE; + goto out; + } + data_ptr = (unsigned long)((char *)(di + 1) + + btrfs_dir_name_len(leaf, di)); + read_extent_buffer(leaf, buffer, data_ptr, + btrfs_dir_name_len(leaf, di)); + ret = btrfs_dir_data_len(leaf, di); + +out: + mutex_unlock(&root->fs_info->fs_mutex); + kfree(name); + btrfs_free_path(path); + return ret; +} + +int btrfs_xattr_set(struct inode *inode, int name_index, + const char *attr_name, const void *value, size_t size, + int flags) +{ + struct btrfs_dir_item *di; + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_trans_handle *trans; + struct btrfs_path *path; + struct xattr_handler *handler = btrfs_xattr_handler(name_index); + char *name; + int ret = 0, mod = 0; + + if (!handler) + return -EOPNOTSUPP; + + /* just in case... */ + if (*attr_name == '\0') + return -EINVAL; + + name = get_name(attr_name, name_index); + if (!name) + return -ENOMEM; + + path = btrfs_alloc_path(); + if (!path) { + kfree(name); + return -ENOMEM; + } + + mutex_lock(&root->fs_info->fs_mutex); + trans = btrfs_start_transaction(root, 1); + btrfs_set_trans_block_group(trans, inode); + + /* first lets see if we already have this xattr */ + di = btrfs_lookup_xattr(trans, root, path, inode->i_ino, name, + strlen(name), -1); + if (IS_ERR(di)) { + ret = PTR_ERR(di); + goto out; + } + + /* ok we already have this xattr, lets remove it */ + if (di) { + /* if we want create only exit */ + if (flags & XATTR_CREATE) { + ret = -EEXIST; + goto out; + } + + ret = btrfs_delete_one_dir_name(trans, root, path, di); + if (ret) + goto out; + btrfs_release_path(root, path); + + /* if we don't have a value then we are removing the xattr */ + if (!value) { + mod = 1; + goto out; + } + } else if (flags & XATTR_REPLACE) { + /* we couldn't find the attr to replace, so error out */ + ret = -ENODATA; + goto out; + } + + /* ok we have to create a completely new xattr */ + ret = btrfs_insert_xattr_item(trans, root, name, strlen(name), + value, size, inode->i_ino); + if (ret) + goto out; + mod = 1; + +out: + if (mod) { + inode->i_ctime = CURRENT_TIME; + ret = btrfs_update_inode(trans, root, inode); + } + + btrfs_end_transaction(trans, root); + mutex_unlock(&root->fs_info->fs_mutex); + kfree(name); + btrfs_free_path(path); + + return ret; +} + +ssize_t btrfs_listxattr(struct dentry *dentry, char *buffer, size_t size) +{ + struct btrfs_key key, found_key; + struct inode *inode = dentry->d_inode; + struct btrfs_root *root = BTRFS_I(inode)->root; + struct btrfs_path *path; + struct btrfs_item *item; + struct extent_buffer *leaf; + struct btrfs_dir_item *di; + struct xattr_handler *handler; + int ret = 0, slot, advance; + size_t total_size = 0, size_left = size, written; + unsigned long name_ptr; + char *name; + u32 nritems; + + /* + * ok we want all objects associated with this id. + * NOTE: we set key.offset = 0; because we want to start with the + * first xattr that we find and walk forward + */ + key.objectid = inode->i_ino; + btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY); + key.offset = 0; + + path = btrfs_alloc_path(); + path->reada = 2; + if (!path) + return -ENOMEM; + + mutex_lock(&root->fs_info->fs_mutex); + + /* search for our xattrs */ + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + goto err; + ret = 0; + advance = 0; + while (1) { + leaf = path->nodes[0]; + nritems = btrfs_header_nritems(leaf); + slot = path->slots[0]; + + /* this is where we start walking through the path */ + if (advance || slot >= nritems) { + /* + * if we've reached the last slot in this leaf we need + * to go to the next leaf and reset everything + */ + if (slot >= nritems-1) { + ret = btrfs_next_leaf(root, path); + if (ret) + break; + leaf = path->nodes[0]; + nritems = btrfs_header_nritems(leaf); + slot = path->slots[0]; + } else { + /* + * just walking through the slots on this leaf + */ + slot++; + path->slots[0]++; + } + } + advance = 1; + + item = btrfs_item_nr(leaf, slot); + btrfs_item_key_to_cpu(leaf, &found_key, slot); + + /* check to make sure this item is what we want */ + if (found_key.objectid != key.objectid) + break; + if (btrfs_key_type(&found_key) != BTRFS_XATTR_ITEM_KEY) + break; + + di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item); + + total_size += btrfs_dir_name_len(leaf, di)+1; + + /* we are just looking for how big our buffer needs to be */ + if (!size) + continue; + + /* find our handler for this xattr */ + name_ptr = (unsigned long)(di + 1); + handler = find_btrfs_xattr_handler(leaf, name_ptr, + btrfs_dir_name_len(leaf, di)); + if (!handler) { + printk(KERN_ERR "btrfs: unsupported xattr found\n"); + continue; + } + + name = kmalloc(btrfs_dir_name_len(leaf, di), GFP_KERNEL); + read_extent_buffer(leaf, name, name_ptr, + btrfs_dir_name_len(leaf, di)); + + /* call the list function associated with this xattr */ + written = handler->list(inode, buffer, size_left, name, + btrfs_dir_name_len(leaf, di)); + kfree(name); + + if (written < 0) { + ret = -ERANGE; + break; + } + + size_left -= written; + buffer += written; + } + ret = total_size; + +err: + mutex_unlock(&root->fs_info->fs_mutex); + btrfs_free_path(path); + + return ret; +} + +/* + * delete all the xattrs associated with the inode. fs_mutex should be + * held when we come into here + */ +int btrfs_delete_xattrs(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct inode *inode) +{ + struct btrfs_path *path; + struct btrfs_key key, found_key; + struct btrfs_item *item; + struct extent_buffer *leaf; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + key.objectid = inode->i_ino; + btrfs_set_key_type(&key, BTRFS_XATTR_ITEM_KEY); + key.offset = (u64)-1; + + while(1) { + /* look for our next xattr */ + ret = btrfs_search_slot(trans, root, &key, path, -1, 1); + if (ret < 0) + goto out; + BUG_ON(ret == 0); + + if (path->slots[0] == 0) + break; + + path->slots[0]--; + leaf = path->nodes[0]; + item = btrfs_item_nr(leaf, path->slots[0]); + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + + if (found_key.objectid != key.objectid) + break; + if (btrfs_key_type(&found_key) != BTRFS_XATTR_ITEM_KEY) + break; + + ret = btrfs_del_item(trans, root, path); + BUG_ON(ret); + btrfs_release_path(root, path); + } + ret = 0; +out: + btrfs_free_path(path); + + return ret; +} + +/* + * Handler functions + */ +#define BTRFS_XATTR_SETGET_FUNCS(name, index) \ +static int btrfs_xattr_##name##_get(struct inode *inode, \ + const char *name, void *value, \ + size_t size) \ +{ \ + return btrfs_xattr_get(inode, index, name, value, size); \ +} \ +static int btrfs_xattr_##name##_set(struct inode *inode, \ + const char *name, const void *value,\ + size_t size, int flags) \ +{ \ + return btrfs_xattr_set(inode, index, name, value, size, flags); \ +} \ + +BTRFS_XATTR_SETGET_FUNCS(security, BTRFS_XATTR_INDEX_SECURITY); +BTRFS_XATTR_SETGET_FUNCS(system, BTRFS_XATTR_INDEX_SYSTEM); +BTRFS_XATTR_SETGET_FUNCS(user, BTRFS_XATTR_INDEX_USER); +BTRFS_XATTR_SETGET_FUNCS(trusted, BTRFS_XATTR_INDEX_TRUSTED); + +struct xattr_handler btrfs_xattr_security_handler = { + .prefix = XATTR_SECURITY_PREFIX, + .list = btrfs_xattr_generic_list, + .get = btrfs_xattr_security_get, + .set = btrfs_xattr_security_set, +}; + +struct xattr_handler btrfs_xattr_system_handler = { + .prefix = XATTR_SYSTEM_PREFIX, + .list = btrfs_xattr_generic_list, + .get = btrfs_xattr_system_get, + .set = btrfs_xattr_system_set, +}; + +struct xattr_handler btrfs_xattr_user_handler = { + .prefix = XATTR_USER_PREFIX, + .list = btrfs_xattr_generic_list, + .get = btrfs_xattr_user_get, + .set = btrfs_xattr_user_set, +}; + +struct xattr_handler btrfs_xattr_trusted_handler = { + .prefix = XATTR_USER_PREFIX, + .list = btrfs_xattr_generic_list, + .get = btrfs_xattr_trusted_get, + .set = btrfs_xattr_trusted_set, +}; diff --git a/fs/btrfs/xattr.h b/fs/btrfs/xattr.h new file mode 100644 index 0000000..b2e47e3 --- /dev/null +++ b/fs/btrfs/xattr.h @@ -0,0 +1,58 @@ +/* + * Copyright (C) 2007 Red Hat. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * 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, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#ifndef __XATTR__ +#define __XATTR__ + +#include +#include "ctree.h" + +/* Name indexes */ +enum { + BTRFS_XATTR_INDEX_USER, + BTRFS_XATTR_INDEX_POSIX_ACL_ACCESS, + BTRFS_XATTR_INDEX_POSIX_ACL_DEFAULT, + BTRFS_XATTR_INDEX_TRUSTED, + BTRFS_XATTR_INDEX_SECURITY, + BTRFS_XATTR_INDEX_SYSTEM, + BTRFS_XATTR_INDEX_END, +}; + +extern struct xattr_handler btrfs_xattr_user_handler; +extern struct xattr_handler btrfs_xattr_trusted_handler; +extern struct xattr_handler btrfs_xattr_acl_access_handler; +extern struct xattr_handler btrfs_xattr_acl_default_handler; +extern struct xattr_handler btrfs_xattr_security_handler; +extern struct xattr_handler btrfs_xattr_system_handler; + +extern struct xattr_handler *btrfs_xattr_handlers[]; + +ssize_t btrfs_xattr_get(struct inode *inode, int name_index, const char *name, + void *buffer, size_t size); +int btrfs_xattr_set(struct inode *inode, int name_index, const char *name, + const void *value, size_t size, int flags); + +/* + * the only reason this is public is for acl.c. There may be a point where + * acl.c doesn't need it, and if thats the case we need to remove it and make + * it static in xattr.c + */ +size_t btrfs_xattr_generic_list(struct inode *inode, char *list, + size_t list_size, const char *name, + size_t name_len); +#endif /* __XATTR__ */ -- 1.8.2.3