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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * Copyright (C) 1992, 1993, 1994, 19954 * Remy Card (card@masi.ibp.fr)5 * Laboratoire MASI - Institut Blaise Pascal6 * Universite Pierre et Marie Curie (Paris VI)7 *8 *  from9 *10 *  linux/include/linux/minix_fs.h11 *12 *  Copyright (C) 1991, 1992  Linus Torvalds13 */14#include <linux/fs.h>15#include <linux/ext2_fs.h>16#include <linux/blockgroup_lock.h>17#include <linux/percpu_counter.h>18#include <linux/rbtree.h>19#include <linux/mm.h>20#include <linux/highmem.h>21 22/* XXX Here for now... not interested in restructing headers JUST now */23 24/* data type for block offset of block group */25typedef int ext2_grpblk_t;26 27/* data type for filesystem-wide blocks number */28typedef unsigned long ext2_fsblk_t;29 30#define E2FSBLK "%lu"31 32struct ext2_reserve_window {33	ext2_fsblk_t		_rsv_start;	/* First byte reserved */34	ext2_fsblk_t		_rsv_end;	/* Last byte reserved or 0 */35};36 37struct ext2_reserve_window_node {38	struct rb_node	 	rsv_node;39	__u32			rsv_goal_size;40	__u32			rsv_alloc_hit;41	struct ext2_reserve_window	rsv_window;42};43 44struct ext2_block_alloc_info {45	/* information about reservation window */46	struct ext2_reserve_window_node	rsv_window_node;47	/*48	 * was i_next_alloc_block in ext2_inode_info49	 * is the logical (file-relative) number of the50	 * most-recently-allocated block in this file.51	 * We use this for detecting linearly ascending allocation requests.52	 */53	__u32			last_alloc_logical_block;54	/*55	 * Was i_next_alloc_goal in ext2_inode_info56	 * is the *physical* companion to i_next_alloc_block.57	 * it is the physical block number of the block which was most-recently58	 * allocated to this file.  This gives us the goal (target) for the next59	 * allocation when we detect linearly ascending requests.60	 */61	ext2_fsblk_t		last_alloc_physical_block;62};63 64#define rsv_start rsv_window._rsv_start65#define rsv_end rsv_window._rsv_end66 67struct mb_cache;68 69/*70 * second extended-fs super-block data in memory71 */72struct ext2_sb_info {73	unsigned long s_inodes_per_block;/* Number of inodes per block */74	unsigned long s_blocks_per_group;/* Number of blocks in a group */75	unsigned long s_inodes_per_group;/* Number of inodes in a group */76	unsigned long s_itb_per_group;	/* Number of inode table blocks per group */77	unsigned long s_gdb_count;	/* Number of group descriptor blocks */78	unsigned long s_desc_per_block;	/* Number of group descriptors per block */79	unsigned long s_groups_count;	/* Number of groups in the fs */80	unsigned long s_overhead_last;  /* Last calculated overhead */81	unsigned long s_blocks_last;    /* Last seen block count */82	struct buffer_head * s_sbh;	/* Buffer containing the super block */83	struct ext2_super_block * s_es;	/* Pointer to the super block in the buffer */84	struct buffer_head ** s_group_desc;85	unsigned long  s_mount_opt;86	unsigned long s_sb_block;87	kuid_t s_resuid;88	kgid_t s_resgid;89	unsigned short s_mount_state;90	unsigned short s_pad;91	int s_addr_per_block_bits;92	int s_desc_per_block_bits;93	int s_inode_size;94	int s_first_ino;95	spinlock_t s_next_gen_lock;96	u32 s_next_generation;97	unsigned long s_dir_count;98	u8 *s_debts;99	struct percpu_counter s_freeblocks_counter;100	struct percpu_counter s_freeinodes_counter;101	struct percpu_counter s_dirs_counter;102	struct blockgroup_lock *s_blockgroup_lock;103	/* root of the per fs reservation window tree */104	spinlock_t s_rsv_window_lock;105	struct rb_root s_rsv_window_root;106	struct ext2_reserve_window_node s_rsv_window_head;107	/*108	 * s_lock protects against concurrent modifications of s_mount_state,109	 * s_blocks_last, s_overhead_last and the content of superblock's110	 * buffer pointed to by sbi->s_es.111	 *112	 * Note: It is used in ext2_show_options() to provide a consistent view113	 * of the mount options.114	 */115	spinlock_t s_lock;116	struct mb_cache *s_ea_block_cache;117	struct dax_device *s_daxdev;118	u64 s_dax_part_off;119};120 121static inline spinlock_t *122sb_bgl_lock(struct ext2_sb_info *sbi, unsigned int block_group)123{124	return bgl_lock_ptr(sbi->s_blockgroup_lock, block_group);125}126 127/*128 * Define EXT2FS_DEBUG to produce debug messages129 */130#undef EXT2FS_DEBUG131 132/*133 * Define EXT2_RESERVATION to reserve data blocks for expanding files134 */135#define EXT2_DEFAULT_RESERVE_BLOCKS     8136/*max window size: 1024(direct blocks) + 3([t,d]indirect blocks) */137#define EXT2_MAX_RESERVE_BLOCKS         1027138#define EXT2_RESERVE_WINDOW_NOT_ALLOCATED 0139/*140 * The second extended file system version141 */142#define EXT2FS_DATE		"95/08/09"143#define EXT2FS_VERSION		"0.5b"144 145/*146 * Debug code147 */148#ifdef EXT2FS_DEBUG149#	define ext2_debug(f, a...)	{ \150					printk ("EXT2-fs DEBUG (%s, %d): %s:", \151						__FILE__, __LINE__, __func__); \152				  	printk (f, ## a); \153					}154#else155#	define ext2_debug(f, a...)	/**/156#endif157 158/*159 * Special inode numbers160 */161#define	EXT2_BAD_INO		 1	/* Bad blocks inode */162#define EXT2_ROOT_INO		 2	/* Root inode */163#define EXT2_BOOT_LOADER_INO	 5	/* Boot loader inode */164#define EXT2_UNDEL_DIR_INO	 6	/* Undelete directory inode */165 166/* First non-reserved inode for old ext2 filesystems */167#define EXT2_GOOD_OLD_FIRST_INO	11168 169static inline struct ext2_sb_info *EXT2_SB(struct super_block *sb)170{171	return sb->s_fs_info;172}173 174/*175 * Macro-instructions used to manage several block sizes176 */177#define EXT2_MIN_BLOCK_SIZE		1024178#define	EXT2_MAX_BLOCK_SIZE		65536179#define EXT2_MIN_BLOCK_LOG_SIZE		  10180#define EXT2_MAX_BLOCK_LOG_SIZE		  16181#define EXT2_BLOCK_SIZE(s)		((s)->s_blocksize)182#define	EXT2_ADDR_PER_BLOCK(s)		(EXT2_BLOCK_SIZE(s) / sizeof (__u32))183#define EXT2_BLOCK_SIZE_BITS(s)		((s)->s_blocksize_bits)184#define	EXT2_ADDR_PER_BLOCK_BITS(s)	(EXT2_SB(s)->s_addr_per_block_bits)185#define EXT2_INODE_SIZE(s)		(EXT2_SB(s)->s_inode_size)186#define EXT2_FIRST_INO(s)		(EXT2_SB(s)->s_first_ino)187 188/*189 * Structure of a blocks group descriptor190 */191struct ext2_group_desc192{193	__le32	bg_block_bitmap;		/* Blocks bitmap block */194	__le32	bg_inode_bitmap;		/* Inodes bitmap block */195	__le32	bg_inode_table;		/* Inodes table block */196	__le16	bg_free_blocks_count;	/* Free blocks count */197	__le16	bg_free_inodes_count;	/* Free inodes count */198	__le16	bg_used_dirs_count;	/* Directories count */199	__le16	bg_pad;200	__le32	bg_reserved[3];201};202 203/*204 * Macro-instructions used to manage group descriptors205 */206#define EXT2_BLOCKS_PER_GROUP(s)	(EXT2_SB(s)->s_blocks_per_group)207#define EXT2_DESC_PER_BLOCK(s)		(EXT2_SB(s)->s_desc_per_block)208#define EXT2_INODES_PER_GROUP(s)	(EXT2_SB(s)->s_inodes_per_group)209#define EXT2_DESC_PER_BLOCK_BITS(s)	(EXT2_SB(s)->s_desc_per_block_bits)210 211/*212 * Constants relative to the data blocks213 */214#define	EXT2_NDIR_BLOCKS		12215#define	EXT2_IND_BLOCK			EXT2_NDIR_BLOCKS216#define	EXT2_DIND_BLOCK			(EXT2_IND_BLOCK + 1)217#define	EXT2_TIND_BLOCK			(EXT2_DIND_BLOCK + 1)218#define	EXT2_N_BLOCKS			(EXT2_TIND_BLOCK + 1)219 220/*221 * Inode flags (GETFLAGS/SETFLAGS)222 */223#define	EXT2_SECRM_FL			FS_SECRM_FL	/* Secure deletion */224#define	EXT2_UNRM_FL			FS_UNRM_FL	/* Undelete */225#define	EXT2_COMPR_FL			FS_COMPR_FL	/* Compress file */226#define EXT2_SYNC_FL			FS_SYNC_FL	/* Synchronous updates */227#define EXT2_IMMUTABLE_FL		FS_IMMUTABLE_FL	/* Immutable file */228#define EXT2_APPEND_FL			FS_APPEND_FL	/* writes to file may only append */229#define EXT2_NODUMP_FL			FS_NODUMP_FL	/* do not dump file */230#define EXT2_NOATIME_FL			FS_NOATIME_FL	/* do not update atime */231/* Reserved for compression usage... */232#define EXT2_DIRTY_FL			FS_DIRTY_FL233#define EXT2_COMPRBLK_FL		FS_COMPRBLK_FL	/* One or more compressed clusters */234#define EXT2_NOCOMP_FL			FS_NOCOMP_FL	/* Don't compress */235#define EXT2_ECOMPR_FL			FS_ECOMPR_FL	/* Compression error */236/* End compression flags --- maybe not all used */	237#define EXT2_BTREE_FL			FS_BTREE_FL	/* btree format dir */238#define EXT2_INDEX_FL			FS_INDEX_FL	/* hash-indexed directory */239#define EXT2_IMAGIC_FL			FS_IMAGIC_FL	/* AFS directory */240#define EXT2_JOURNAL_DATA_FL		FS_JOURNAL_DATA_FL /* Reserved for ext3 */241#define EXT2_NOTAIL_FL			FS_NOTAIL_FL	/* file tail should not be merged */242#define EXT2_DIRSYNC_FL			FS_DIRSYNC_FL	/* dirsync behaviour (directories only) */243#define EXT2_TOPDIR_FL			FS_TOPDIR_FL	/* Top of directory hierarchies*/244#define EXT2_RESERVED_FL		FS_RESERVED_FL	/* reserved for ext2 lib */245 246#define EXT2_FL_USER_VISIBLE		FS_FL_USER_VISIBLE	/* User visible flags */247#define EXT2_FL_USER_MODIFIABLE		FS_FL_USER_MODIFIABLE	/* User modifiable flags */248 249/* Flags that should be inherited by new inodes from their parent. */250#define EXT2_FL_INHERITED (EXT2_SECRM_FL | EXT2_UNRM_FL | EXT2_COMPR_FL |\251			   EXT2_SYNC_FL | EXT2_NODUMP_FL |\252			   EXT2_NOATIME_FL | EXT2_COMPRBLK_FL |\253			   EXT2_NOCOMP_FL | EXT2_JOURNAL_DATA_FL |\254			   EXT2_NOTAIL_FL | EXT2_DIRSYNC_FL)255 256/* Flags that are appropriate for regular files (all but dir-specific ones). */257#define EXT2_REG_FLMASK (~(EXT2_DIRSYNC_FL | EXT2_TOPDIR_FL))258 259/* Flags that are appropriate for non-directories/regular files. */260#define EXT2_OTHER_FLMASK (EXT2_NODUMP_FL | EXT2_NOATIME_FL)261 262/* Mask out flags that are inappropriate for the given type of inode. */263static inline __u32 ext2_mask_flags(umode_t mode, __u32 flags)264{265	if (S_ISDIR(mode))266		return flags;267	else if (S_ISREG(mode))268		return flags & EXT2_REG_FLMASK;269	else270		return flags & EXT2_OTHER_FLMASK;271}272 273/*274 * ioctl commands275 */276#define	EXT2_IOC_GETVERSION		FS_IOC_GETVERSION277#define	EXT2_IOC_SETVERSION		FS_IOC_SETVERSION278#define	EXT2_IOC_GETRSVSZ		_IOR('f', 5, long)279#define	EXT2_IOC_SETRSVSZ		_IOW('f', 6, long)280 281/*282 * ioctl commands in 32 bit emulation283 */284#define EXT2_IOC32_GETVERSION		FS_IOC32_GETVERSION285#define EXT2_IOC32_SETVERSION		FS_IOC32_SETVERSION286 287/*288 * Structure of an inode on the disk289 */290struct ext2_inode {291	__le16	i_mode;		/* File mode */292	__le16	i_uid;		/* Low 16 bits of Owner Uid */293	__le32	i_size;		/* Size in bytes */294	__le32	i_atime;	/* Access time */295	__le32	i_ctime;	/* Creation time */296	__le32	i_mtime;	/* Modification time */297	__le32	i_dtime;	/* Deletion Time */298	__le16	i_gid;		/* Low 16 bits of Group Id */299	__le16	i_links_count;	/* Links count */300	__le32	i_blocks;	/* Blocks count */301	__le32	i_flags;	/* File flags */302	union {303		struct {304			__le32  l_i_reserved1;305		} linux1;306		struct {307			__le32  h_i_translator;308		} hurd1;309		struct {310			__le32  m_i_reserved1;311		} masix1;312	} osd1;				/* OS dependent 1 */313	__le32	i_block[EXT2_N_BLOCKS];/* Pointers to blocks */314	__le32	i_generation;	/* File version (for NFS) */315	__le32	i_file_acl;	/* File ACL */316	__le32	i_dir_acl;	/* Directory ACL */317	__le32	i_faddr;	/* Fragment address */318	union {319		struct {320			__u8	l_i_frag;	/* Fragment number */321			__u8	l_i_fsize;	/* Fragment size */322			__u16	i_pad1;323			__le16	l_i_uid_high;	/* these 2 fields    */324			__le16	l_i_gid_high;	/* were reserved2[0] */325			__u32	l_i_reserved2;326		} linux2;327		struct {328			__u8	h_i_frag;	/* Fragment number */329			__u8	h_i_fsize;	/* Fragment size */330			__le16	h_i_mode_high;331			__le16	h_i_uid_high;332			__le16	h_i_gid_high;333			__le32	h_i_author;334		} hurd2;335		struct {336			__u8	m_i_frag;	/* Fragment number */337			__u8	m_i_fsize;	/* Fragment size */338			__u16	m_pad1;339			__u32	m_i_reserved2[2];340		} masix2;341	} osd2;				/* OS dependent 2 */342};343 344#define i_size_high	i_dir_acl345 346#define i_reserved1	osd1.linux1.l_i_reserved1347#define i_frag		osd2.linux2.l_i_frag348#define i_fsize		osd2.linux2.l_i_fsize349#define i_uid_low	i_uid350#define i_gid_low	i_gid351#define i_uid_high	osd2.linux2.l_i_uid_high352#define i_gid_high	osd2.linux2.l_i_gid_high353#define i_reserved2	osd2.linux2.l_i_reserved2354 355/*356 * File system states357 */358#define	EXT2_VALID_FS			0x0001	/* Unmounted cleanly */359#define	EXT2_ERROR_FS			0x0002	/* Errors detected */360#define	EFSCORRUPTED			EUCLEAN	/* Filesystem is corrupted */361 362/*363 * Mount flags364 */365#define EXT2_MOUNT_OLDALLOC		0x000002  /* Don't use the new Orlov allocator */366#define EXT2_MOUNT_GRPID		0x000004  /* Create files with directory's group */367#define EXT2_MOUNT_DEBUG		0x000008  /* Some debugging messages */368#define EXT2_MOUNT_ERRORS_CONT		0x000010  /* Continue on errors */369#define EXT2_MOUNT_ERRORS_RO		0x000020  /* Remount fs ro on errors */370#define EXT2_MOUNT_ERRORS_PANIC		0x000040  /* Panic on errors */371#define EXT2_MOUNT_MINIX_DF		0x000080  /* Mimics the Minix statfs */372#define EXT2_MOUNT_NOBH			0x000100  /* No buffer_heads */373#define EXT2_MOUNT_NO_UID32		0x000200  /* Disable 32-bit UIDs */374#define EXT2_MOUNT_XATTR_USER		0x004000  /* Extended user attributes */375#define EXT2_MOUNT_POSIX_ACL		0x008000  /* POSIX Access Control Lists */376#define EXT2_MOUNT_XIP			0x010000  /* Obsolete, use DAX */377#define EXT2_MOUNT_USRQUOTA		0x020000  /* user quota */378#define EXT2_MOUNT_GRPQUOTA		0x040000  /* group quota */379#define EXT2_MOUNT_RESERVATION		0x080000  /* Preallocation */380#define EXT2_MOUNT_DAX			0x100000  /* Direct Access */381 382 383#define clear_opt(o, opt)		o &= ~EXT2_MOUNT_##opt384#define set_opt(o, opt)			o |= EXT2_MOUNT_##opt385#define test_opt(sb, opt)		(EXT2_SB(sb)->s_mount_opt & \386					 EXT2_MOUNT_##opt)387/*388 * Maximal mount counts between two filesystem checks389 */390#define EXT2_DFL_MAX_MNT_COUNT		20	/* Allow 20 mounts */391#define EXT2_DFL_CHECKINTERVAL		0	/* Don't use interval check */392 393/*394 * Behaviour when detecting errors395 */396#define EXT2_ERRORS_CONTINUE		1	/* Continue execution */397#define EXT2_ERRORS_RO			2	/* Remount fs read-only */398#define EXT2_ERRORS_PANIC		3	/* Panic */399#define EXT2_ERRORS_DEFAULT		EXT2_ERRORS_CONTINUE400 401/*402 * Allocation flags403 */404#define EXT2_ALLOC_NORESERVE            0x1	/* Do not use reservation405						 * window for allocation */406 407/*408 * Structure of the super block409 */410struct ext2_super_block {411	__le32	s_inodes_count;		/* Inodes count */412	__le32	s_blocks_count;		/* Blocks count */413	__le32	s_r_blocks_count;	/* Reserved blocks count */414	__le32	s_free_blocks_count;	/* Free blocks count */415	__le32	s_free_inodes_count;	/* Free inodes count */416	__le32	s_first_data_block;	/* First Data Block */417	__le32	s_log_block_size;	/* Block size */418	__le32	s_log_frag_size;	/* Fragment size */419	__le32	s_blocks_per_group;	/* # Blocks per group */420	__le32	s_frags_per_group;	/* # Fragments per group */421	__le32	s_inodes_per_group;	/* # Inodes per group */422	__le32	s_mtime;		/* Mount time */423	__le32	s_wtime;		/* Write time */424	__le16	s_mnt_count;		/* Mount count */425	__le16	s_max_mnt_count;	/* Maximal mount count */426	__le16	s_magic;		/* Magic signature */427	__le16	s_state;		/* File system state */428	__le16	s_errors;		/* Behaviour when detecting errors */429	__le16	s_minor_rev_level; 	/* minor revision level */430	__le32	s_lastcheck;		/* time of last check */431	__le32	s_checkinterval;	/* max. time between checks */432	__le32	s_creator_os;		/* OS */433	__le32	s_rev_level;		/* Revision level */434	__le16	s_def_resuid;		/* Default uid for reserved blocks */435	__le16	s_def_resgid;		/* Default gid for reserved blocks */436	/*437	 * These fields are for EXT2_DYNAMIC_REV superblocks only.438	 *439	 * Note: the difference between the compatible feature set and440	 * the incompatible feature set is that if there is a bit set441	 * in the incompatible feature set that the kernel doesn't442	 * know about, it should refuse to mount the filesystem.443	 * 444	 * e2fsck's requirements are more strict; if it doesn't know445	 * about a feature in either the compatible or incompatible446	 * feature set, it must abort and not try to meddle with447	 * things it doesn't understand...448	 */449	__le32	s_first_ino; 		/* First non-reserved inode */450	__le16   s_inode_size; 		/* size of inode structure */451	__le16	s_block_group_nr; 	/* block group # of this superblock */452	__le32	s_feature_compat; 	/* compatible feature set */453	__le32	s_feature_incompat; 	/* incompatible feature set */454	__le32	s_feature_ro_compat; 	/* readonly-compatible feature set */455	__u8	s_uuid[16];		/* 128-bit uuid for volume */456	char	s_volume_name[16]; 	/* volume name */457	char	s_last_mounted[64]; 	/* directory where last mounted */458	__le32	s_algorithm_usage_bitmap; /* For compression */459	/*460	 * Performance hints.  Directory preallocation should only461	 * happen if the EXT2_COMPAT_PREALLOC flag is on.462	 */463	__u8	s_prealloc_blocks;	/* Nr of blocks to try to preallocate*/464	__u8	s_prealloc_dir_blocks;	/* Nr to preallocate for dirs */465	__u16	s_padding1;466	/*467	 * Journaling support valid if EXT3_FEATURE_COMPAT_HAS_JOURNAL set.468	 */469	__u8	s_journal_uuid[16];	/* uuid of journal superblock */470	__u32	s_journal_inum;		/* inode number of journal file */471	__u32	s_journal_dev;		/* device number of journal file */472	__u32	s_last_orphan;		/* start of list of inodes to delete */473	__u32	s_hash_seed[4];		/* HTREE hash seed */474	__u8	s_def_hash_version;	/* Default hash version to use */475	__u8	s_reserved_char_pad;476	__u16	s_reserved_word_pad;477	__le32	s_default_mount_opts;478 	__le32	s_first_meta_bg; 	/* First metablock block group */479	__u32	s_reserved[190];	/* Padding to the end of the block */480};481 482/*483 * Codes for operating systems484 */485#define EXT2_OS_LINUX		0486#define EXT2_OS_HURD		1487#define EXT2_OS_MASIX		2488#define EXT2_OS_FREEBSD		3489#define EXT2_OS_LITES		4490 491/*492 * Revision levels493 */494#define EXT2_GOOD_OLD_REV	0	/* The good old (original) format */495#define EXT2_DYNAMIC_REV	1 	/* V2 format w/ dynamic inode sizes */496 497#define EXT2_CURRENT_REV	EXT2_GOOD_OLD_REV498#define EXT2_MAX_SUPP_REV	EXT2_DYNAMIC_REV499 500#define EXT2_GOOD_OLD_INODE_SIZE 128501 502/*503 * Feature set definitions504 */505 506#define EXT2_HAS_COMPAT_FEATURE(sb,mask)			\507	( EXT2_SB(sb)->s_es->s_feature_compat & cpu_to_le32(mask) )508#define EXT2_HAS_RO_COMPAT_FEATURE(sb,mask)			\509	( EXT2_SB(sb)->s_es->s_feature_ro_compat & cpu_to_le32(mask) )510#define EXT2_HAS_INCOMPAT_FEATURE(sb,mask)			\511	( EXT2_SB(sb)->s_es->s_feature_incompat & cpu_to_le32(mask) )512#define EXT2_SET_COMPAT_FEATURE(sb,mask)			\513	EXT2_SB(sb)->s_es->s_feature_compat |= cpu_to_le32(mask)514#define EXT2_SET_RO_COMPAT_FEATURE(sb,mask)			\515	EXT2_SB(sb)->s_es->s_feature_ro_compat |= cpu_to_le32(mask)516#define EXT2_SET_INCOMPAT_FEATURE(sb,mask)			\517	EXT2_SB(sb)->s_es->s_feature_incompat |= cpu_to_le32(mask)518#define EXT2_CLEAR_COMPAT_FEATURE(sb,mask)			\519	EXT2_SB(sb)->s_es->s_feature_compat &= ~cpu_to_le32(mask)520#define EXT2_CLEAR_RO_COMPAT_FEATURE(sb,mask)			\521	EXT2_SB(sb)->s_es->s_feature_ro_compat &= ~cpu_to_le32(mask)522#define EXT2_CLEAR_INCOMPAT_FEATURE(sb,mask)			\523	EXT2_SB(sb)->s_es->s_feature_incompat &= ~cpu_to_le32(mask)524 525#define EXT2_FEATURE_COMPAT_DIR_PREALLOC	0x0001526#define EXT2_FEATURE_COMPAT_IMAGIC_INODES	0x0002527#define EXT3_FEATURE_COMPAT_HAS_JOURNAL		0x0004528#define EXT2_FEATURE_COMPAT_EXT_ATTR		0x0008529#define EXT2_FEATURE_COMPAT_RESIZE_INO		0x0010530#define EXT2_FEATURE_COMPAT_DIR_INDEX		0x0020531#define EXT2_FEATURE_COMPAT_ANY			0xffffffff532 533#define EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER	0x0001534#define EXT2_FEATURE_RO_COMPAT_LARGE_FILE	0x0002535#define EXT2_FEATURE_RO_COMPAT_BTREE_DIR	0x0004536#define EXT2_FEATURE_RO_COMPAT_ANY		0xffffffff537 538#define EXT2_FEATURE_INCOMPAT_COMPRESSION	0x0001539#define EXT2_FEATURE_INCOMPAT_FILETYPE		0x0002540#define EXT3_FEATURE_INCOMPAT_RECOVER		0x0004541#define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV	0x0008542#define EXT2_FEATURE_INCOMPAT_META_BG		0x0010543#define EXT2_FEATURE_INCOMPAT_ANY		0xffffffff544 545#define EXT2_FEATURE_COMPAT_SUPP	EXT2_FEATURE_COMPAT_EXT_ATTR546#define EXT2_FEATURE_INCOMPAT_SUPP	(EXT2_FEATURE_INCOMPAT_FILETYPE| \547					 EXT2_FEATURE_INCOMPAT_META_BG)548#define EXT2_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER| \549					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE| \550					 EXT2_FEATURE_RO_COMPAT_BTREE_DIR)551#define EXT2_FEATURE_RO_COMPAT_UNSUPPORTED	~EXT2_FEATURE_RO_COMPAT_SUPP552#define EXT2_FEATURE_INCOMPAT_UNSUPPORTED	~EXT2_FEATURE_INCOMPAT_SUPP553 554/*555 * Default values for user and/or group using reserved blocks556 */557#define	EXT2_DEF_RESUID		0558#define	EXT2_DEF_RESGID		0559 560/*561 * Default mount options562 */563#define EXT2_DEFM_DEBUG		0x0001564#define EXT2_DEFM_BSDGROUPS	0x0002565#define EXT2_DEFM_XATTR_USER	0x0004566#define EXT2_DEFM_ACL		0x0008567#define EXT2_DEFM_UID16		0x0010568    /* Not used by ext2, but reserved for use by ext3 */569#define EXT3_DEFM_JMODE		0x0060 570#define EXT3_DEFM_JMODE_DATA	0x0020571#define EXT3_DEFM_JMODE_ORDERED	0x0040572#define EXT3_DEFM_JMODE_WBACK	0x0060573 574/*575 * Structure of a directory entry576 */577 578struct ext2_dir_entry {579	__le32	inode;			/* Inode number */580	__le16	rec_len;		/* Directory entry length */581	__le16	name_len;		/* Name length */582	char	name[];			/* File name, up to EXT2_NAME_LEN */583};584 585/*586 * The new version of the directory entry.  Since EXT2 structures are587 * stored in intel byte order, and the name_len field could never be588 * bigger than 255 chars, it's safe to reclaim the extra byte for the589 * file_type field.590 */591struct ext2_dir_entry_2 {592	__le32	inode;			/* Inode number */593	__le16	rec_len;		/* Directory entry length */594	__u8	name_len;		/* Name length */595	__u8	file_type;596	char	name[];			/* File name, up to EXT2_NAME_LEN */597};598 599/*600 * EXT2_DIR_PAD defines the directory entries boundaries601 *602 * NOTE: It must be a multiple of 4603 */604#define EXT2_DIR_PAD		 	4605#define EXT2_DIR_ROUND 			(EXT2_DIR_PAD - 1)606#define EXT2_DIR_REC_LEN(name_len)	(((name_len) + 8 + EXT2_DIR_ROUND) & \607					 ~EXT2_DIR_ROUND)608#define EXT2_MAX_REC_LEN		((1<<16)-1)609 610static inline void verify_offsets(void)611{612#define A(x,y) BUILD_BUG_ON(x != offsetof(struct ext2_super_block, y));613	A(EXT2_SB_MAGIC_OFFSET, s_magic);614	A(EXT2_SB_BLOCKS_OFFSET, s_blocks_count);615	A(EXT2_SB_BSIZE_OFFSET, s_log_block_size);616#undef A617}618 619/*620 * ext2 mount options621 */622struct ext2_mount_options {623	unsigned long s_mount_opt;624	kuid_t s_resuid;625	kgid_t s_resgid;626};627 628/*629 * second extended file system inode data in memory630 */631struct ext2_inode_info {632	__le32	i_data[15];633	__u32	i_flags;634	__u32	i_faddr;635	__u8	i_frag_no;636	__u8	i_frag_size;637	__u16	i_state;638	__u32	i_file_acl;639	__u32	i_dir_acl;640	__u32	i_dtime;641 642	/*643	 * i_block_group is the number of the block group which contains644	 * this file's inode.  Constant across the lifetime of the inode,645	 * it is used for making block allocation decisions - we try to646	 * place a file's data blocks near its inode block, and new inodes647	 * near to their parent directory's inode.648	 */649	__u32	i_block_group;650 651	/* block reservation info */652	struct ext2_block_alloc_info *i_block_alloc_info;653 654	__u32	i_dir_start_lookup;655#ifdef CONFIG_EXT2_FS_XATTR656	/*657	 * Extended attributes can be read independently of the main file658	 * data. Taking i_mutex even when reading would cause contention659	 * between readers of EAs and writers of regular file data, so660	 * instead we synchronize on xattr_sem when reading or changing661	 * EAs.662	 */663	struct rw_semaphore xattr_sem;664#endif665	rwlock_t i_meta_lock;666 667	/*668	 * truncate_mutex is for serialising ext2_truncate() against669	 * ext2_getblock().  It also protects the internals of the inode's670	 * reservation data structures: ext2_reserve_window and671	 * ext2_reserve_window_node.672	 */673	struct mutex truncate_mutex;674	struct inode	vfs_inode;675	struct list_head i_orphan;	/* unlinked but open inodes */676#ifdef CONFIG_QUOTA677	struct dquot __rcu *i_dquot[MAXQUOTAS];678#endif679};680 681/*682 * Inode dynamic state flags683 */684#define EXT2_STATE_NEW			0x00000001 /* inode is newly created */685 686 687/*688 * Function prototypes689 */690 691/*692 * Ok, these declarations are also in <linux/kernel.h> but none of the693 * ext2 source programs needs to include it so they are duplicated here.694 */695 696static inline struct ext2_inode_info *EXT2_I(struct inode *inode)697{698	return container_of(inode, struct ext2_inode_info, vfs_inode);699}700 701/* balloc.c */702extern int ext2_bg_has_super(struct super_block *sb, int group);703extern unsigned long ext2_bg_num_gdb(struct super_block *sb, int group);704extern ext2_fsblk_t ext2_new_blocks(struct inode *, ext2_fsblk_t,705				unsigned long *, int *, unsigned int);706extern int ext2_data_block_valid(struct ext2_sb_info *sbi, ext2_fsblk_t start_blk,707				 unsigned int count);708extern void ext2_free_blocks(struct inode *, ext2_fsblk_t, unsigned long);709extern unsigned long ext2_count_free_blocks (struct super_block *);710extern unsigned long ext2_count_dirs (struct super_block *);711extern struct ext2_group_desc * ext2_get_group_desc(struct super_block * sb,712						    unsigned int block_group,713						    struct buffer_head ** bh);714extern void ext2_discard_reservation (struct inode *);715extern int ext2_should_retry_alloc(struct super_block *sb, int *retries);716extern void ext2_init_block_alloc_info(struct inode *);717extern void ext2_rsv_window_add(struct super_block *sb, struct ext2_reserve_window_node *rsv);718 719/* dir.c */720int ext2_add_link(struct dentry *, struct inode *);721int ext2_inode_by_name(struct inode *dir,722			      const struct qstr *child, ino_t *ino);723int ext2_make_empty(struct inode *, struct inode *);724struct ext2_dir_entry_2 *ext2_find_entry(struct inode *, const struct qstr *,725		struct folio **foliop);726int ext2_delete_entry(struct ext2_dir_entry_2 *dir, struct folio *folio);727int ext2_empty_dir(struct inode *);728struct ext2_dir_entry_2 *ext2_dotdot(struct inode *dir, struct folio **foliop);729int ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,730		struct folio *folio, struct inode *inode, bool update_times);731 732/* ialloc.c */733extern struct inode * ext2_new_inode (struct inode *, umode_t, const struct qstr *);734extern void ext2_free_inode (struct inode *);735extern unsigned long ext2_count_free_inodes (struct super_block *);736extern unsigned long ext2_count_free (struct buffer_head *, unsigned);737 738/* inode.c */739extern struct inode *ext2_iget (struct super_block *, unsigned long);740extern int ext2_write_inode (struct inode *, struct writeback_control *);741extern void ext2_evict_inode(struct inode *);742void ext2_write_failed(struct address_space *mapping, loff_t to);743extern int ext2_get_block(struct inode *, sector_t, struct buffer_head *, int);744extern int ext2_setattr (struct mnt_idmap *, struct dentry *, struct iattr *);745extern int ext2_getattr (struct mnt_idmap *, const struct path *,746			 struct kstat *, u32, unsigned int);747extern void ext2_set_inode_flags(struct inode *inode);748extern int ext2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,749		       u64 start, u64 len);750 751/* ioctl.c */752extern int ext2_fileattr_get(struct dentry *dentry, struct fileattr *fa);753extern int ext2_fileattr_set(struct mnt_idmap *idmap,754			     struct dentry *dentry, struct fileattr *fa);755extern long ext2_ioctl(struct file *, unsigned int, unsigned long);756extern long ext2_compat_ioctl(struct file *, unsigned int, unsigned long);757 758/* namei.c */759struct dentry *ext2_get_parent(struct dentry *child);760 761/* super.c */762extern __printf(3, 4)763void ext2_error(struct super_block *, const char *, const char *, ...);764extern __printf(3, 4)765void ext2_msg(struct super_block *, const char *, const char *, ...);766extern void ext2_update_dynamic_rev (struct super_block *sb);767extern void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,768			    int wait);769 770/*771 * Inodes and files operations772 */773 774/* dir.c */775extern const struct file_operations ext2_dir_operations;776 777/* file.c */778extern int ext2_fsync(struct file *file, loff_t start, loff_t end,779		      int datasync);780extern const struct inode_operations ext2_file_inode_operations;781extern const struct file_operations ext2_file_operations;782 783/* inode.c */784extern void ext2_set_file_ops(struct inode *inode);785extern const struct address_space_operations ext2_aops;786extern const struct iomap_ops ext2_iomap_ops;787 788/* namei.c */789extern const struct inode_operations ext2_dir_inode_operations;790extern const struct inode_operations ext2_special_inode_operations;791 792/* symlink.c */793extern const struct inode_operations ext2_fast_symlink_inode_operations;794extern const struct inode_operations ext2_symlink_inode_operations;795 796static inline ext2_fsblk_t797ext2_group_first_block_no(struct super_block *sb, unsigned long group_no)798{799	return group_no * (ext2_fsblk_t)EXT2_BLOCKS_PER_GROUP(sb) +800		le32_to_cpu(EXT2_SB(sb)->s_es->s_first_data_block);801}802 803static inline ext2_fsblk_t804ext2_group_last_block_no(struct super_block *sb, unsigned long group_no)805{806	struct ext2_sb_info *sbi = EXT2_SB(sb);807 808	if (group_no == sbi->s_groups_count - 1)809		return le32_to_cpu(sbi->s_es->s_blocks_count) - 1;810	else811		return ext2_group_first_block_no(sb, group_no) +812			EXT2_BLOCKS_PER_GROUP(sb) - 1;813}814 815#define ext2_set_bit	__test_and_set_bit_le816#define ext2_clear_bit	__test_and_clear_bit_le817#define ext2_test_bit	test_bit_le818#define ext2_find_first_zero_bit	find_first_zero_bit_le819#define ext2_find_next_zero_bit		find_next_zero_bit_le820