From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- fs/ext4/xattr.h | 212 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 212 insertions(+) create mode 100644 fs/ext4/xattr.h (limited to 'fs/ext4/xattr.h') diff --git a/fs/ext4/xattr.h b/fs/ext4/xattr.h new file mode 100644 index 000000000..f39cad2ab --- /dev/null +++ b/fs/ext4/xattr.h @@ -0,0 +1,212 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + File: fs/ext4/xattr.h + + On-disk format of extended attributes for the ext4 filesystem. + + (C) 2001 Andreas Gruenbacher, +*/ + +#include + +/* Magic value in attribute blocks */ +#define EXT4_XATTR_MAGIC 0xEA020000 + +/* Maximum number of references to one attribute block */ +#define EXT4_XATTR_REFCOUNT_MAX 1024 + +/* Name indexes */ +#define EXT4_XATTR_INDEX_USER 1 +#define EXT4_XATTR_INDEX_POSIX_ACL_ACCESS 2 +#define EXT4_XATTR_INDEX_POSIX_ACL_DEFAULT 3 +#define EXT4_XATTR_INDEX_TRUSTED 4 +#define EXT4_XATTR_INDEX_LUSTRE 5 +#define EXT4_XATTR_INDEX_SECURITY 6 +#define EXT4_XATTR_INDEX_SYSTEM 7 +#define EXT4_XATTR_INDEX_RICHACL 8 +#define EXT4_XATTR_INDEX_ENCRYPTION 9 +#define EXT4_XATTR_INDEX_HURD 10 /* Reserved for Hurd */ + +struct ext4_xattr_header { + __le32 h_magic; /* magic number for identification */ + __le32 h_refcount; /* reference count */ + __le32 h_blocks; /* number of disk blocks used */ + __le32 h_hash; /* hash value of all attributes */ + __le32 h_checksum; /* crc32c(uuid+id+xattrblock) */ + /* id = inum if refcount=1, blknum otherwise */ + __u32 h_reserved[3]; /* zero right now */ +}; + +struct ext4_xattr_ibody_header { + __le32 h_magic; /* magic number for identification */ +}; + +struct ext4_xattr_entry { + __u8 e_name_len; /* length of name */ + __u8 e_name_index; /* attribute name index */ + __le16 e_value_offs; /* offset in disk block of value */ + __le32 e_value_inum; /* inode in which the value is stored */ + __le32 e_value_size; /* size of attribute value */ + __le32 e_hash; /* hash value of name and value */ + char e_name[0]; /* attribute name */ +}; + +#define EXT4_XATTR_PAD_BITS 2 +#define EXT4_XATTR_PAD (1<e_name_len))) +#define EXT4_XATTR_SIZE(size) \ + (((size) + EXT4_XATTR_ROUND) & ~EXT4_XATTR_ROUND) + +#define IHDR(inode, raw_inode) \ + ((struct ext4_xattr_ibody_header *) \ + ((void *)raw_inode + \ + EXT4_GOOD_OLD_INODE_SIZE + \ + EXT4_I(inode)->i_extra_isize)) +#define IFIRST(hdr) ((struct ext4_xattr_entry *)((hdr)+1)) + +/* + * XATTR_SIZE_MAX is currently 64k, but for the purposes of checking + * for file system consistency errors, we use a somewhat bigger value. + * This allows XATTR_SIZE_MAX to grow in the future, but by using this + * instead of INT_MAX for certain consistency checks, we don't need to + * worry about arithmetic overflows. (Actually XATTR_SIZE_MAX is + * defined in include/uapi/linux/limits.h, so changing it is going + * not going to be trivial....) + */ +#define EXT4_XATTR_SIZE_MAX (1 << 24) + +/* + * The minimum size of EA value when you start storing it in an external inode + * size of block - size of header - size of 1 entry - 4 null bytes +*/ +#define EXT4_XATTR_MIN_LARGE_EA_SIZE(b) \ + ((b) - EXT4_XATTR_LEN(3) - sizeof(struct ext4_xattr_header) - 4) + +#define BHDR(bh) ((struct ext4_xattr_header *)((bh)->b_data)) +#define ENTRY(ptr) ((struct ext4_xattr_entry *)(ptr)) +#define BFIRST(bh) ENTRY(BHDR(bh)+1) +#define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0) + +#define EXT4_ZERO_XATTR_VALUE ((void *)-1) + +struct ext4_xattr_info { + const char *name; + const void *value; + size_t value_len; + int name_index; + int in_inode; +}; + +struct ext4_xattr_search { + struct ext4_xattr_entry *first; + void *base; + void *end; + struct ext4_xattr_entry *here; + int not_found; +}; + +struct ext4_xattr_ibody_find { + struct ext4_xattr_search s; + struct ext4_iloc iloc; +}; + +struct ext4_xattr_inode_array { + unsigned int count; /* # of used items in the array */ + struct inode *inodes[0]; +}; + +extern const struct xattr_handler ext4_xattr_user_handler; +extern const struct xattr_handler ext4_xattr_trusted_handler; +extern const struct xattr_handler ext4_xattr_security_handler; + +#define EXT4_XATTR_NAME_ENCRYPTION_CONTEXT "c" + +/* + * The EXT4_STATE_NO_EXPAND is overloaded and used for two purposes. + * The first is to signal that there the inline xattrs and data are + * taking up so much space that we might as well not keep trying to + * expand it. The second is that xattr_sem is taken for writing, so + * we shouldn't try to recurse into the inode expansion. For this + * second case, we need to make sure that we take save and restore the + * NO_EXPAND state flag appropriately. + */ +static inline void ext4_write_lock_xattr(struct inode *inode, int *save) +{ + down_write(&EXT4_I(inode)->xattr_sem); + *save = ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND); + ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); +} + +static inline int ext4_write_trylock_xattr(struct inode *inode, int *save) +{ + if (down_write_trylock(&EXT4_I(inode)->xattr_sem) == 0) + return 0; + *save = ext4_test_inode_state(inode, EXT4_STATE_NO_EXPAND); + ext4_set_inode_state(inode, EXT4_STATE_NO_EXPAND); + return 1; +} + +static inline void ext4_write_unlock_xattr(struct inode *inode, int *save) +{ + if (*save == 0) + ext4_clear_inode_state(inode, EXT4_STATE_NO_EXPAND); + up_write(&EXT4_I(inode)->xattr_sem); +} + +extern ssize_t ext4_listxattr(struct dentry *, char *, size_t); + +extern int ext4_xattr_get(struct inode *, int, const char *, void *, size_t); +extern int ext4_xattr_set(struct inode *, int, const char *, const void *, size_t, int); +extern int ext4_xattr_set_handle(handle_t *, struct inode *, int, const char *, const void *, size_t, int); +extern int ext4_xattr_set_credits(struct inode *inode, size_t value_len, + bool is_create, int *credits); +extern int __ext4_xattr_set_credits(struct super_block *sb, struct inode *inode, + struct buffer_head *block_bh, size_t value_len, + bool is_create); + +extern int ext4_xattr_delete_inode(handle_t *handle, struct inode *inode, + struct ext4_xattr_inode_array **array, + int extra_credits); +extern void ext4_xattr_inode_array_free(struct ext4_xattr_inode_array *array); + +extern int ext4_expand_extra_isize_ea(struct inode *inode, int new_extra_isize, + struct ext4_inode *raw_inode, handle_t *handle); + +extern const struct xattr_handler *ext4_xattr_handlers[]; + +extern int ext4_xattr_ibody_find(struct inode *inode, struct ext4_xattr_info *i, + struct ext4_xattr_ibody_find *is); +extern int ext4_xattr_ibody_get(struct inode *inode, int name_index, + const char *name, + void *buffer, size_t buffer_size); +extern int ext4_xattr_ibody_inline_set(handle_t *handle, struct inode *inode, + struct ext4_xattr_info *i, + struct ext4_xattr_ibody_find *is); + +extern struct mb_cache *ext4_xattr_create_cache(void); +extern void ext4_xattr_destroy_cache(struct mb_cache *); + +#ifdef CONFIG_EXT4_FS_SECURITY +extern int ext4_init_security(handle_t *handle, struct inode *inode, + struct inode *dir, const struct qstr *qstr); +#else +static inline int ext4_init_security(handle_t *handle, struct inode *inode, + struct inode *dir, const struct qstr *qstr) +{ + return 0; +} +#endif + +#ifdef CONFIG_LOCKDEP +extern void ext4_xattr_inode_set_class(struct inode *ea_inode); +#else +static inline void ext4_xattr_inode_set_class(struct inode *ea_inode) { } +#endif + +extern int ext4_get_inode_usage(struct inode *inode, qsize_t *usage); -- cgit v1.2.3