Import the Linux ext2fs files that our GPL'ed ext2fs files seem to be

based on.

Obtained from:	Linux 1.2.2 distribution
This commit is contained in:
Bruce Evans 2000-01-01 11:05:19 +00:00
commit 6969f4fedf
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/vendor-sys/ext2fs/dist/; revision=55289
7 changed files with 2547 additions and 0 deletions

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/*
* linux/fs/ext2/bitmap.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*/
#include <linux/fs.h>
#include <linux/ext2_fs.h>
static int nibblemap[] = {4, 3, 3, 2, 3, 2, 2, 1, 3, 2, 2, 1, 2, 1, 1, 0};
unsigned long ext2_count_free (struct buffer_head * map, unsigned int numchars)
{
unsigned int i;
unsigned long sum = 0;
if (!map)
return (0);
for (i = 0; i < numchars; i++)
sum += nibblemap[map->b_data[i] & 0xf] +
nibblemap[(map->b_data[i] >> 4) & 0xf];
return (sum);
}

505
sys/gnu/ext2fs/ext2_fs.h Normal file
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/*
* linux/include/linux/ext2_fs.h
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/include/linux/minix_fs.h
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
#ifndef _LINUX_EXT2_FS_H
#define _LINUX_EXT2_FS_H
#include <linux/types.h>
/*
* The second extended filesystem constants/structures
*/
/*
* Define EXT2FS_DEBUG to produce debug messages
*/
#undef EXT2FS_DEBUG
/*
* Define EXT2FS_DEBUG_CACHE to produce cache debug messages
*/
#undef EXT2FS_DEBUG_CACHE
/*
* Define EXT2FS_CHECK_CACHE to add some checks to the name cache code
*/
#undef EXT2FS_CHECK_CACHE
/*
* Define EXT2FS_PRE_02B_COMPAT to convert ext 2 fs prior to 0.2b
*/
#undef EXT2FS_PRE_02B_COMPAT
/*
* Define EXT2_PREALLOCATE to preallocate data blocks for expanding files
*/
#define EXT2_PREALLOCATE
/*
* The second extended file system version
*/
#define EXT2FS_DATE "95/03/19"
#define EXT2FS_VERSION "0.5a"
/*
* Debug code
*/
#ifdef EXT2FS_DEBUG
# define ext2_debug(f, a...) { \
printk ("EXT2-fs DEBUG (%s, %d): %s:", \
__FILE__, __LINE__, __FUNCTION__); \
printk (f, ## a); \
}
#else
# define ext2_debug(f, a...) /**/
#endif
/*
* Special inodes numbers
*/
#define EXT2_BAD_INO 1 /* Bad blocks inode */
#define EXT2_ROOT_INO 2 /* Root inode */
#define EXT2_ACL_IDX_INO 3 /* ACL inode */
#define EXT2_ACL_DATA_INO 4 /* ACL inode */
#define EXT2_BOOT_LOADER_INO 5 /* Boot loader inode */
#define EXT2_UNDEL_DIR_INO 6 /* Undelete directory inode */
#define EXT2_FIRST_INO 11 /* First non reserved inode */
/*
* The second extended file system magic number
*/
#define EXT2_PRE_02B_MAGIC 0xEF51
#define EXT2_SUPER_MAGIC 0xEF53
/*
* Maximal count of links to a file
*/
#define EXT2_LINK_MAX 32000
/*
* Macro-instructions used to manage several block sizes
*/
#define EXT2_MIN_BLOCK_SIZE 1024
#define EXT2_MAX_BLOCK_SIZE 4096
#define EXT2_MIN_BLOCK_LOG_SIZE 10
#ifdef __KERNEL__
# define EXT2_BLOCK_SIZE(s) ((s)->s_blocksize)
#else
# define EXT2_BLOCK_SIZE(s) (EXT2_MIN_BLOCK_SIZE << (s)->s_log_block_size)
#endif
#define EXT2_ACLE_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_acl_entry))
#define EXT2_ADDR_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (__u32))
#ifdef __KERNEL__
# define EXT2_BLOCK_SIZE_BITS(s) ((s)->u.ext2_sb.s_es->s_log_block_size + 10)
#else
# define EXT2_BLOCK_SIZE_BITS(s) ((s)->s_log_block_size + 10)
#endif
#define EXT2_INODES_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_inode))
/*
* Macro-instructions used to manage fragments
*/
#define EXT2_MIN_FRAG_SIZE 1024
#define EXT2_MAX_FRAG_SIZE 4096
#define EXT2_MIN_FRAG_LOG_SIZE 10
#ifdef __KERNEL__
# define EXT2_FRAG_SIZE(s) ((s)->u.ext2_sb.s_frag_size)
# define EXT2_FRAGS_PER_BLOCK(s) ((s)->u.ext2_sb.s_frags_per_block)
#else
# define EXT2_FRAG_SIZE(s) (EXT2_MIN_FRAG_SIZE << (s)->s_log_frag_size)
# define EXT2_FRAGS_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / EXT2_FRAG_SIZE(s))
#endif
/*
* ACL structures
*/
struct ext2_acl_header /* Header of Access Control Lists */
{
__u32 aclh_size;
__u32 aclh_file_count;
__u32 aclh_acle_count;
__u32 aclh_first_acle;
};
struct ext2_acl_entry /* Access Control List Entry */
{
__u32 acle_size;
__u16 acle_perms; /* Access permissions */
__u16 acle_type; /* Type of entry */
__u16 acle_tag; /* User or group identity */
__u16 acle_pad1;
__u32 acle_next; /* Pointer on next entry for the */
/* same inode or on next free entry */
};
/*
* Structure of a blocks group descriptor
*/
struct ext2_old_group_desc
{
__u32 bg_block_bitmap; /* Blocks bitmap block */
__u32 bg_inode_bitmap; /* Inodes bitmap block */
__u32 bg_inode_table; /* Inodes table block */
__u16 bg_free_blocks_count; /* Free blocks count */
__u16 bg_free_inodes_count; /* Free inodes count */
};
struct ext2_group_desc
{
__u32 bg_block_bitmap; /* Blocks bitmap block */
__u32 bg_inode_bitmap; /* Inodes bitmap block */
__u32 bg_inode_table; /* Inodes table block */
__u16 bg_free_blocks_count; /* Free blocks count */
__u16 bg_free_inodes_count; /* Free inodes count */
__u16 bg_used_dirs_count; /* Directories count */
__u16 bg_pad;
__u32 bg_reserved[3];
};
/*
* Macro-instructions used to manage group descriptors
*/
#ifdef __KERNEL__
# define EXT2_BLOCKS_PER_GROUP(s) ((s)->u.ext2_sb.s_blocks_per_group)
# define EXT2_DESC_PER_BLOCK(s) ((s)->u.ext2_sb.s_desc_per_block)
# define EXT2_INODES_PER_GROUP(s) ((s)->u.ext2_sb.s_inodes_per_group)
#else
# define EXT2_BLOCKS_PER_GROUP(s) ((s)->s_blocks_per_group)
# define EXT2_DESC_PER_BLOCK(s) (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
# define EXT2_INODES_PER_GROUP(s) ((s)->s_inodes_per_group)
#endif
/*
* Constants relative to the data blocks
*/
#define EXT2_NDIR_BLOCKS 12
#define EXT2_IND_BLOCK EXT2_NDIR_BLOCKS
#define EXT2_DIND_BLOCK (EXT2_IND_BLOCK + 1)
#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
/*
* Inode flags
*/
#define EXT2_SECRM_FL 0x00000001 /* Secure deletion */
#define EXT2_UNRM_FL 0x00000002 /* Undelete */
#define EXT2_COMPR_FL 0x00000004 /* Compress file */
#define EXT2_SYNC_FL 0x00000008 /* Synchronous updates */
#define EXT2_IMMUTABLE_FL 0x00000010 /* Immutable file */
#define EXT2_APPEND_FL 0x00000020 /* writes to file may only append */
#define EXT2_NODUMP_FL 0x00000040 /* do not dump file */
/*
* ioctl commands
*/
#define EXT2_IOC_GETFLAGS _IOR('f', 1, long)
#define EXT2_IOC_SETFLAGS _IOW('f', 2, long)
#define EXT2_IOC_GETVERSION _IOR('v', 1, long)
#define EXT2_IOC_SETVERSION _IOW('v', 2, long)
/*
* Structure of an inode on the disk
*/
struct ext2_inode {
__u16 i_mode; /* File mode */
__u16 i_uid; /* Owner Uid */
__u32 i_size; /* Size in bytes */
__u32 i_atime; /* Access time */
__u32 i_ctime; /* Creation time */
__u32 i_mtime; /* Modification time */
__u32 i_dtime; /* Deletion Time */
__u16 i_gid; /* Group Id */
__u16 i_links_count; /* Links count */
__u32 i_blocks; /* Blocks count */
__u32 i_flags; /* File flags */
union {
struct {
__u32 l_i_reserved1;
} linux1;
struct {
__u32 h_i_translator;
} hurd1;
struct {
__u32 m_i_reserved1;
} masix1;
} osd1; /* OS dependent 1 */
__u32 i_block[EXT2_N_BLOCKS];/* Pointers to blocks */
__u32 i_version; /* File version (for NFS) */
__u32 i_file_acl; /* File ACL */
__u32 i_dir_acl; /* Directory ACL */
__u32 i_faddr; /* Fragment address */
union {
struct {
__u8 l_i_frag; /* Fragment number */
__u8 l_i_fsize; /* Fragment size */
__u16 i_pad1;
__u32 l_i_reserved2[2];
} linux2;
struct {
__u8 h_i_frag; /* Fragment number */
__u8 h_i_fsize; /* Fragment size */
__u16 h_i_mode_high;
__u16 h_i_uid_high;
__u16 h_i_gid_high;
__u32 h_i_author;
} hurd2;
struct {
__u8 m_i_frag; /* Fragment number */
__u8 m_i_fsize; /* Fragment size */
__u16 m_pad1;
__u32 m_i_reserved2[2];
} masix2;
} osd2; /* OS dependent 2 */
};
#if defined(__KERNEL__) || defined(__linux__)
#define i_reserved1 osd1.linux1.l_i_reserved1
#define i_frag osd2.linux2.l_i_frag
#define i_fsize osd2.linux2.l_i_fsize
#define i_reserved2 osd2.linux2.l_i_reserved2
#endif
#ifdef __hurd__
#define i_translator osd1.hurd1.h_i_translator
#define i_frag osd2.hurd2.h_i_frag;
#define i_fsize osd2.hurd2.h_i_fsize;
#define i_uid_high osd2.hurd2.h_i_uid_high
#define i_gid_high osd2.hurd2.h_i_gid_high
#define i_author osd2.hurd2.h_i_author
#endif
#ifdef __masix__
#define i_reserved1 osd1.masix1.m_i_reserved1
#define i_frag osd2.masix2.m_i_frag
#define i_fsize osd2.masix2.m_i_fsize
#define i_reserved2 osd2.masix2.m_i_reserved2
#endif
/*
* File system states
*/
#define EXT2_VALID_FS 0x0001 /* Unmounted cleanly */
#define EXT2_ERROR_FS 0x0002 /* Errors detected */
/*
* Mount flags
*/
#define EXT2_MOUNT_CHECK_NORMAL 0x0001 /* Do some more checks */
#define EXT2_MOUNT_CHECK_STRICT 0x0002 /* Do again more checks */
#define EXT2_MOUNT_CHECK (EXT2_MOUNT_CHECK_NORMAL | \
EXT2_MOUNT_CHECK_STRICT)
#define EXT2_MOUNT_GRPID 0x0004 /* Create files with directory's group */
#define EXT2_MOUNT_DEBUG 0x0008 /* Some debugging messages */
#define EXT2_MOUNT_ERRORS_CONT 0x0010 /* Continue on errors */
#define EXT2_MOUNT_ERRORS_RO 0x0020 /* Remount fs ro on errors */
#define EXT2_MOUNT_ERRORS_PANIC 0x0040 /* Panic on errors */
#define EXT2_MOUNT_MINIX_DF 0x0080 /* Mimics the Minix statfs */
#define clear_opt(o, opt) o &= ~EXT2_MOUNT_##opt
#define set_opt(o, opt) o |= EXT2_MOUNT_##opt
#define test_opt(sb, opt) ((sb)->u.ext2_sb.s_mount_opt & \
EXT2_MOUNT_##opt)
/*
* Maximal mount counts between two filesystem checks
*/
#define EXT2_DFL_MAX_MNT_COUNT 20 /* Allow 20 mounts */
#define EXT2_DFL_CHECKINTERVAL 0 /* Don't use interval check */
/*
* Behaviour when detecting errors
*/
#define EXT2_ERRORS_CONTINUE 1 /* Continue execution */
#define EXT2_ERRORS_RO 2 /* Remount fs read-only */
#define EXT2_ERRORS_PANIC 3 /* Panic */
#define EXT2_ERRORS_DEFAULT EXT2_ERRORS_CONTINUE
/*
* Structure of the super block
*/
struct ext2_super_block {
__u32 s_inodes_count; /* Inodes count */
__u32 s_blocks_count; /* Blocks count */
__u32 s_r_blocks_count; /* Reserved blocks count */
__u32 s_free_blocks_count; /* Free blocks count */
__u32 s_free_inodes_count; /* Free inodes count */
__u32 s_first_data_block; /* First Data Block */
__u32 s_log_block_size; /* Block size */
__s32 s_log_frag_size; /* Fragment size */
__u32 s_blocks_per_group; /* # Blocks per group */
__u32 s_frags_per_group; /* # Fragments per group */
__u32 s_inodes_per_group; /* # Inodes per group */
__u32 s_mtime; /* Mount time */
__u32 s_wtime; /* Write time */
__u16 s_mnt_count; /* Mount count */
__s16 s_max_mnt_count; /* Maximal mount count */
__u16 s_magic; /* Magic signature */
__u16 s_state; /* File system state */
__u16 s_errors; /* Behaviour when detecting errors */
__u16 s_pad;
__u32 s_lastcheck; /* time of last check */
__u32 s_checkinterval; /* max. time between checks */
__u32 s_creator_os; /* OS */
__u32 s_rev_level; /* Revision level */
__u16 s_def_resuid; /* Default uid for reserved blocks */
__u16 s_def_resgid; /* Default gid for reserved blocks */
__u32 s_reserved[235]; /* Padding to the end of the block */
};
#define EXT2_OS_LINUX 0
#define EXT2_OS_HURD 1
#define EXT2_OS_MASIX 2
#define EXT2_CURRENT_REV 0
#define EXT2_DEF_RESUID 0
#define EXT2_DEF_RESGID 0
/*
* Structure of a directory entry
*/
#define EXT2_NAME_LEN 255
struct ext2_dir_entry {
__u32 inode; /* Inode number */
__u16 rec_len; /* Directory entry length */
__u16 name_len; /* Name length */
char name[EXT2_NAME_LEN]; /* File name */
};
/*
* EXT2_DIR_PAD defines the directory entries boundaries
*
* NOTE: It must be a multiple of 4
*/
#define EXT2_DIR_PAD 4
#define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1)
#define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \
~EXT2_DIR_ROUND)
#ifdef __KERNEL__
/*
* Function prototypes
*/
/*
* Ok, these declarations are also in <linux/kernel.h> but none of the
* ext2 source programs needs to include it so they are duplicated here.
*/
#if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5)
# define NORET_TYPE __volatile__
# define ATTRIB_NORET /**/
# define NORET_AND /**/
#else
# define NORET_TYPE /**/
# define ATTRIB_NORET __attribute__((noreturn))
# define NORET_AND noreturn,
#endif
/* acl.c */
extern int ext2_permission (struct inode *, int);
/* balloc.c */
extern int ext2_new_block (struct super_block *, unsigned long,
__u32 *, __u32 *);
extern void ext2_free_blocks (struct super_block *, unsigned long,
unsigned long);
extern unsigned long ext2_count_free_blocks (struct super_block *);
extern void ext2_check_blocks_bitmap (struct super_block *);
/* bitmap.c */
extern unsigned long ext2_count_free (struct buffer_head *, unsigned);
/* dir.c */
extern int ext2_check_dir_entry (char *, struct inode *,
struct ext2_dir_entry *, struct buffer_head *,
unsigned long);
/* file.c */
extern int ext2_read (struct inode *, struct file *, char *, int);
extern int ext2_write (struct inode *, struct file *, char *, int);
/* fsync.c */
extern int ext2_sync_file (struct inode *, struct file *);
/* ialloc.c */
extern struct inode * ext2_new_inode (const struct inode *, int);
extern void ext2_free_inode (struct inode *);
extern unsigned long ext2_count_free_inodes (struct super_block *);
extern void ext2_check_inodes_bitmap (struct super_block *);
/* inode.c */
extern int ext2_bmap (struct inode *, int);
extern struct buffer_head * ext2_getblk (struct inode *, long, int, int *);
extern struct buffer_head * ext2_bread (struct inode *, int, int, int *);
extern int ext2_getcluster (struct inode * inode, long block);
extern void ext2_read_inode (struct inode *);
extern void ext2_write_inode (struct inode *);
extern void ext2_put_inode (struct inode *);
extern int ext2_sync_inode (struct inode *);
extern void ext2_discard_prealloc (struct inode *);
/* ioctl.c */
extern int ext2_ioctl (struct inode *, struct file *, unsigned int,
unsigned long);
/* namei.c */
extern void ext2_release (struct inode *, struct file *);
extern int ext2_lookup (struct inode *,const char *, int, struct inode **);
extern int ext2_create (struct inode *,const char *, int, int,
struct inode **);
extern int ext2_mkdir (struct inode *, const char *, int, int);
extern int ext2_rmdir (struct inode *, const char *, int);
extern int ext2_unlink (struct inode *, const char *, int);
extern int ext2_symlink (struct inode *, const char *, int, const char *);
extern int ext2_link (struct inode *, struct inode *, const char *, int);
extern int ext2_mknod (struct inode *, const char *, int, int, int);
extern int ext2_rename (struct inode *, const char *, int,
struct inode *, const char *, int);
/* super.c */
extern void ext2_error (struct super_block *, const char *, const char *, ...)
__attribute__ ((format (printf, 3, 4)));
extern NORET_TYPE void ext2_panic (struct super_block *, const char *,
const char *, ...)
__attribute__ ((NORET_AND format (printf, 3, 4)));
extern void ext2_warning (struct super_block *, const char *, const char *, ...)
__attribute__ ((format (printf, 3, 4)));
extern void ext2_put_super (struct super_block *);
extern void ext2_write_super (struct super_block *);
extern int ext2_remount (struct super_block *, int *, char *);
extern struct super_block * ext2_read_super (struct super_block *,void *,int);
extern void ext2_statfs (struct super_block *, struct statfs *);
/* truncate.c */
extern void ext2_truncate (struct inode *);
/*
* Inodes and files operations
*/
/* dir.c */
extern struct inode_operations ext2_dir_inode_operations;
/* file.c */
extern struct inode_operations ext2_file_inode_operations;
/* symlink.c */
extern struct inode_operations ext2_symlink_inode_operations;
#endif /* __KERNEL__ */
#endif /* _LINUX_EXT2_FS_H */

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/*
* linux/include/linux/ext2_fs_i.h
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/include/linux/minix_fs_i.h
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
#ifndef _LINUX_EXT2_FS_I
#define _LINUX_EXT2_FS_I
/*
* second extended file system inode data in memory
*/
struct ext2_inode_info {
__u32 i_data[15];
__u32 i_flags;
__u32 i_faddr;
__u8 i_frag_no;
__u8 i_frag_size;
__u16 i_osync;
__u32 i_file_acl;
__u32 i_dir_acl;
__u32 i_dtime;
__u32 i_version;
__u32 i_block_group;
__u32 i_next_alloc_block;
__u32 i_next_alloc_goal;
__u32 i_prealloc_block;
__u32 i_prealloc_count;
};
#endif /* _LINUX_EXT2_FS_I */

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/*
* linux/include/linux/ext2_fs_sb.h
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/include/linux/minix_fs_sb.h
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
#ifndef _LINUX_EXT2_FS_SB
#define _LINUX_EXT2_FS_SB
/*
* The following is not needed anymore since the descriptors buffer
* heads are now dynamically allocated
*/
/* #define EXT2_MAX_GROUP_DESC 8 */
#define EXT2_MAX_GROUP_LOADED 8
/*
* second extended-fs super-block data in memory
*/
struct ext2_sb_info {
unsigned long s_frag_size; /* Size of a fragment in bytes */
unsigned long s_frags_per_block;/* Number of fragments per block */
unsigned long s_inodes_per_block;/* Number of inodes per block */
unsigned long s_frags_per_group;/* Number of fragments in a group */
unsigned long s_blocks_per_group;/* Number of blocks in a group */
unsigned long s_inodes_per_group;/* Number of inodes in a group */
unsigned long s_itb_per_group; /* Number of inode table blocks per group */
unsigned long s_db_per_group; /* Number of descriptor blocks per group */
unsigned long s_desc_per_block; /* Number of group descriptors per block */
unsigned long s_groups_count; /* Number of groups in the fs */
struct buffer_head * s_sbh; /* Buffer containing the super block */
struct ext2_super_block * s_es; /* Pointer to the super block in the buffer */
struct buffer_head ** s_group_desc;
unsigned short s_loaded_inode_bitmaps;
unsigned short s_loaded_block_bitmaps;
unsigned long s_inode_bitmap_number[EXT2_MAX_GROUP_LOADED];
struct buffer_head * s_inode_bitmap[EXT2_MAX_GROUP_LOADED];
unsigned long s_block_bitmap_number[EXT2_MAX_GROUP_LOADED];
struct buffer_head * s_block_bitmap[EXT2_MAX_GROUP_LOADED];
int s_rename_lock;
struct wait_queue * s_rename_wait;
unsigned long s_mount_opt;
unsigned short s_resuid;
unsigned short s_resgid;
unsigned short s_mount_state;
};
#endif /* _LINUX_EXT2_FS_SB */

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/*
* linux/fs/ext2/balloc.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* Enhanced block allocation by Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
*/
/*
* balloc.c contains the blocks allocation and deallocation routines
*/
/*
* The free blocks are managed by bitmaps. A file system contains several
* blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
* block for inodes, N blocks for the inode table and data blocks.
*
* The file system contains group descriptors which are located after the
* super block. Each descriptor contains the number of the bitmap block and
* the free blocks count in the block. The descriptors are loaded in memory
* when a file system is mounted (see ext2_read_super).
*/
#include <linux/fs.h>
#include <linux/ext2_fs.h>
#include <linux/stat.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <linux/locks.h>
#include <asm/bitops.h>
#define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1)
static struct ext2_group_desc * get_group_desc (struct super_block * sb,
unsigned int block_group,
struct buffer_head ** bh)
{
unsigned long group_desc;
unsigned long desc;
struct ext2_group_desc * gdp;
if (block_group >= sb->u.ext2_sb.s_groups_count)
ext2_panic (sb, "get_group_desc",
"block_group >= groups_count - "
"block_group = %d, groups_count = %lu",
block_group, sb->u.ext2_sb.s_groups_count);
group_desc = block_group / EXT2_DESC_PER_BLOCK(sb);
desc = block_group % EXT2_DESC_PER_BLOCK(sb);
if (!sb->u.ext2_sb.s_group_desc[group_desc])
ext2_panic (sb, "get_group_desc",
"Group descriptor not loaded - "
"block_group = %d, group_desc = %lu, desc = %lu",
block_group, group_desc, desc);
gdp = (struct ext2_group_desc *)
sb->u.ext2_sb.s_group_desc[group_desc]->b_data;
if (bh)
*bh = sb->u.ext2_sb.s_group_desc[group_desc];
return gdp + desc;
}
static void read_block_bitmap (struct super_block * sb,
unsigned int block_group,
unsigned long bitmap_nr)
{
struct ext2_group_desc * gdp;
struct buffer_head * bh;
gdp = get_group_desc (sb, block_group, NULL);
bh = bread (sb->s_dev, gdp->bg_block_bitmap, sb->s_blocksize);
if (!bh)
ext2_panic (sb, "read_block_bitmap",
"Cannot read block bitmap - "
"block_group = %d, block_bitmap = %lu",
block_group, (unsigned long) gdp->bg_block_bitmap);
sb->u.ext2_sb.s_block_bitmap_number[bitmap_nr] = block_group;
sb->u.ext2_sb.s_block_bitmap[bitmap_nr] = bh;
}
/*
* load_block_bitmap loads the block bitmap for a blocks group
*
* It maintains a cache for the last bitmaps loaded. This cache is managed
* with a LRU algorithm.
*
* Notes:
* 1/ There is one cache per mounted file system.
* 2/ If the file system contains less than EXT2_MAX_GROUP_LOADED groups,
* this function reads the bitmap without maintaining a LRU cache.
*/
static int load__block_bitmap (struct super_block * sb,
unsigned int block_group)
{
int i, j;
unsigned long block_bitmap_number;
struct buffer_head * block_bitmap;
if (block_group >= sb->u.ext2_sb.s_groups_count)
ext2_panic (sb, "load_block_bitmap",
"block_group >= groups_count - "
"block_group = %d, groups_count = %lu",
block_group, sb->u.ext2_sb.s_groups_count);
if (sb->u.ext2_sb.s_groups_count <= EXT2_MAX_GROUP_LOADED) {
if (sb->u.ext2_sb.s_block_bitmap[block_group]) {
if (sb->u.ext2_sb.s_block_bitmap_number[block_group] !=
block_group)
ext2_panic (sb, "load_block_bitmap",
"block_group != block_bitmap_number");
else
return block_group;
} else {
read_block_bitmap (sb, block_group, block_group);
return block_group;
}
}
for (i = 0; i < sb->u.ext2_sb.s_loaded_block_bitmaps &&
sb->u.ext2_sb.s_block_bitmap_number[i] != block_group; i++)
;
if (i < sb->u.ext2_sb.s_loaded_block_bitmaps &&
sb->u.ext2_sb.s_block_bitmap_number[i] == block_group) {
block_bitmap_number = sb->u.ext2_sb.s_block_bitmap_number[i];
block_bitmap = sb->u.ext2_sb.s_block_bitmap[i];
for (j = i; j > 0; j--) {
sb->u.ext2_sb.s_block_bitmap_number[j] =
sb->u.ext2_sb.s_block_bitmap_number[j - 1];
sb->u.ext2_sb.s_block_bitmap[j] =
sb->u.ext2_sb.s_block_bitmap[j - 1];
}
sb->u.ext2_sb.s_block_bitmap_number[0] = block_bitmap_number;
sb->u.ext2_sb.s_block_bitmap[0] = block_bitmap;
} else {
if (sb->u.ext2_sb.s_loaded_block_bitmaps < EXT2_MAX_GROUP_LOADED)
sb->u.ext2_sb.s_loaded_block_bitmaps++;
else
brelse (sb->u.ext2_sb.s_block_bitmap[EXT2_MAX_GROUP_LOADED - 1]);
for (j = sb->u.ext2_sb.s_loaded_block_bitmaps - 1; j > 0; j--) {
sb->u.ext2_sb.s_block_bitmap_number[j] =
sb->u.ext2_sb.s_block_bitmap_number[j - 1];
sb->u.ext2_sb.s_block_bitmap[j] =
sb->u.ext2_sb.s_block_bitmap[j - 1];
}
read_block_bitmap (sb, block_group, 0);
}
return 0;
}
static inline int load_block_bitmap (struct super_block * sb,
unsigned int block_group)
{
if (sb->u.ext2_sb.s_loaded_block_bitmaps > 0 &&
sb->u.ext2_sb.s_block_bitmap_number[0] == block_group)
return 0;
if (sb->u.ext2_sb.s_groups_count <= EXT2_MAX_GROUP_LOADED &&
sb->u.ext2_sb.s_block_bitmap_number[block_group] == block_group &&
sb->u.ext2_sb.s_block_bitmap[block_group])
return block_group;
return load__block_bitmap (sb, block_group);
}
void ext2_free_blocks (struct super_block * sb, unsigned long block,
unsigned long count)
{
struct buffer_head * bh;
struct buffer_head * bh2;
unsigned long block_group;
unsigned long bit;
unsigned long i;
int bitmap_nr;
struct ext2_group_desc * gdp;
struct ext2_super_block * es;
if (!sb) {
printk ("ext2_free_blocks: nonexistent device");
return;
}
lock_super (sb);
es = sb->u.ext2_sb.s_es;
if (block < es->s_first_data_block ||
(block + count) > es->s_blocks_count) {
ext2_error (sb, "ext2_free_blocks",
"Freeing blocks not in datazone - "
"block = %lu, count = %lu", block, count);
unlock_super (sb);
return;
}
ext2_debug ("freeing block %lu\n", block);
block_group = (block - es->s_first_data_block) /
EXT2_BLOCKS_PER_GROUP(sb);
bit = (block - es->s_first_data_block) % EXT2_BLOCKS_PER_GROUP(sb);
if (bit + count > EXT2_BLOCKS_PER_GROUP(sb))
ext2_panic (sb, "ext2_free_blocks",
"Freeing blocks across group boundary - "
"Block = %lu, count = %lu",
block, count);
bitmap_nr = load_block_bitmap (sb, block_group);
bh = sb->u.ext2_sb.s_block_bitmap[bitmap_nr];
gdp = get_group_desc (sb, block_group, &bh2);
if (test_opt (sb, CHECK_STRICT) &&
(in_range (gdp->bg_block_bitmap, block, count) ||
in_range (gdp->bg_inode_bitmap, block, count) ||
in_range (block, gdp->bg_inode_table,
sb->u.ext2_sb.s_itb_per_group) ||
in_range (block + count - 1, gdp->bg_inode_table,
sb->u.ext2_sb.s_itb_per_group)))
ext2_panic (sb, "ext2_free_blocks",
"Freeing blocks in system zones - "
"Block = %lu, count = %lu",
block, count);
for (i = 0; i < count; i++) {
if (!clear_bit (bit + i, bh->b_data))
ext2_warning (sb, "ext2_free_blocks",
"bit already cleared for block %lu",
block);
else {
gdp->bg_free_blocks_count++;
es->s_free_blocks_count++;
}
}
mark_buffer_dirty(bh2, 1);
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
mark_buffer_dirty(bh, 1);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
sb->s_dirt = 1;
unlock_super (sb);
return;
}
/*
* ext2_new_block uses a goal block to assist allocation. If the goal is
* free, or there is a free block within 32 blocks of the goal, that block
* is allocated. Otherwise a forward search is made for a free block; within
* each block group the search first looks for an entire free byte in the block
* bitmap, and then for any free bit if that fails.
*/
int ext2_new_block (struct super_block * sb, unsigned long goal,
u32 * prealloc_count,
u32 * prealloc_block)
{
struct buffer_head * bh;
struct buffer_head * bh2;
char * p, * r;
int i, j, k, tmp;
unsigned long lmap;
int bitmap_nr;
struct ext2_group_desc * gdp;
struct ext2_super_block * es;
#ifdef EXT2FS_DEBUG
static int goal_hits = 0, goal_attempts = 0;
#endif
if (!sb) {
printk ("ext2_new_block: nonexistent device");
return 0;
}
lock_super (sb);
es = sb->u.ext2_sb.s_es;
if (es->s_free_blocks_count <= es->s_r_blocks_count &&
(!fsuser() && (sb->u.ext2_sb.s_resuid != current->fsuid) &&
(sb->u.ext2_sb.s_resgid == 0 ||
!in_group_p (sb->u.ext2_sb.s_resgid)))) {
unlock_super (sb);
return 0;
}
ext2_debug ("goal=%lu.\n", goal);
repeat:
/*
* First, test whether the goal block is free.
*/
if (goal < es->s_first_data_block || goal >= es->s_blocks_count)
goal = es->s_first_data_block;
i = (goal - es->s_first_data_block) / EXT2_BLOCKS_PER_GROUP(sb);
gdp = get_group_desc (sb, i, &bh2);
if (gdp->bg_free_blocks_count > 0) {
j = ((goal - es->s_first_data_block) % EXT2_BLOCKS_PER_GROUP(sb));
#ifdef EXT2FS_DEBUG
if (j)
goal_attempts++;
#endif
bitmap_nr = load_block_bitmap (sb, i);
bh = sb->u.ext2_sb.s_block_bitmap[bitmap_nr];
ext2_debug ("goal is at %d:%d.\n", i, j);
if (!test_bit(j, bh->b_data)) {
#ifdef EXT2FS_DEBUG
goal_hits++;
ext2_debug ("goal bit allocated.\n");
#endif
goto got_block;
}
if (j) {
/*
* The goal was occupied; search forward for a free
* block within the next 32 blocks
*/
lmap = ((((unsigned long *) bh->b_data)[j >> 5]) >>
((j & 31) + 1));
if (j < EXT2_BLOCKS_PER_GROUP(sb) - 32)
lmap |= (((unsigned long *) bh->b_data)[(j >> 5) + 1]) <<
(31 - (j & 31));
else
lmap |= 0xffffffff << (31 - (j & 31));
if (lmap != 0xffffffffl) {
k = ffz(lmap) + 1;
if ((j + k) < EXT2_BLOCKS_PER_GROUP(sb)) {
j += k;
goto got_block;
}
}
}
ext2_debug ("Bit not found near goal\n");
/*
* There has been no free block found in the near vicinity
* of the goal: do a search forward through the block groups,
* searching in each group first for an entire free byte in
* the bitmap and then for any free bit.
*
* Search first in the remainder of the current group; then,
* cyclicly search through the rest of the groups.
*/
p = ((char *) bh->b_data) + (j >> 3);
r = memscan(p, 0, (EXT2_BLOCKS_PER_GROUP(sb) - j + 7) >> 3);
k = (r - ((char *) bh->b_data)) << 3;
if (k < EXT2_BLOCKS_PER_GROUP(sb)) {
j = k;
goto search_back;
}
k = find_next_zero_bit ((unsigned long *) bh->b_data,
EXT2_BLOCKS_PER_GROUP(sb),
j);
if (k < EXT2_BLOCKS_PER_GROUP(sb)) {
j = k;
goto got_block;
}
}
ext2_debug ("Bit not found in block group %d.\n", i);
/*
* Now search the rest of the groups. We assume that
* i and gdp correctly point to the last group visited.
*/
for (k = 0; k < sb->u.ext2_sb.s_groups_count; k++) {
i++;
if (i >= sb->u.ext2_sb.s_groups_count)
i = 0;
gdp = get_group_desc (sb, i, &bh2);
if (gdp->bg_free_blocks_count > 0)
break;
}
if (k >= sb->u.ext2_sb.s_groups_count) {
unlock_super (sb);
return 0;
}
bitmap_nr = load_block_bitmap (sb, i);
bh = sb->u.ext2_sb.s_block_bitmap[bitmap_nr];
r = memscan(bh->b_data, 0, EXT2_BLOCKS_PER_GROUP(sb) >> 3);
j = (r - bh->b_data) << 3;
if (j < EXT2_BLOCKS_PER_GROUP(sb))
goto search_back;
else
j = find_first_zero_bit ((unsigned long *) bh->b_data,
EXT2_BLOCKS_PER_GROUP(sb));
if (j >= EXT2_BLOCKS_PER_GROUP(sb)) {
ext2_error (sb, "ext2_new_block",
"Free blocks count corrupted for block group %d", i);
unlock_super (sb);
return 0;
}
search_back:
/*
* We have succeeded in finding a free byte in the block
* bitmap. Now search backwards up to 7 bits to find the
* start of this group of free blocks.
*/
for (k = 0; k < 7 && j > 0 && !test_bit (j - 1, bh->b_data); k++, j--);
got_block:
ext2_debug ("using block group %d(%d)\n", i, gdp->bg_free_blocks_count);
tmp = j + i * EXT2_BLOCKS_PER_GROUP(sb) + es->s_first_data_block;
if (test_opt (sb, CHECK_STRICT) &&
(tmp == gdp->bg_block_bitmap ||
tmp == gdp->bg_inode_bitmap ||
in_range (tmp, gdp->bg_inode_table, sb->u.ext2_sb.s_itb_per_group)))
ext2_panic (sb, "ext2_new_block",
"Allocating block in system zone - "
"block = %u", tmp);
if (set_bit (j, bh->b_data)) {
ext2_warning (sb, "ext2_new_block",
"bit already set for block %d", j);
goto repeat;
}
ext2_debug ("found bit %d\n", j);
/*
* Do block preallocation now if required.
*/
#ifdef EXT2_PREALLOCATE
if (prealloc_block) {
*prealloc_count = 0;
*prealloc_block = tmp + 1;
for (k = 1;
k < 8 && (j + k) < EXT2_BLOCKS_PER_GROUP(sb); k++) {
if (set_bit (j + k, bh->b_data))
break;
(*prealloc_count)++;
}
gdp->bg_free_blocks_count -= *prealloc_count;
es->s_free_blocks_count -= *prealloc_count;
ext2_debug ("Preallocated a further %lu bits.\n",
*prealloc_count);
}
#endif
j = tmp;
mark_buffer_dirty(bh, 1);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
if (j >= es->s_blocks_count) {
ext2_error (sb, "ext2_new_block",
"block >= blocks count - "
"block_group = %d, block=%d", i, j);
unlock_super (sb);
return 0;
}
if (!(bh = getblk (sb->s_dev, j, sb->s_blocksize))) {
ext2_error (sb, "ext2_new_block", "cannot get block %d", j);
unlock_super (sb);
return 0;
}
memset(bh->b_data, 0, sb->s_blocksize);
bh->b_uptodate = 1;
mark_buffer_dirty(bh, 1);
brelse (bh);
ext2_debug ("allocating block %d. "
"Goal hits %d of %d.\n", j, goal_hits, goal_attempts);
gdp->bg_free_blocks_count--;
mark_buffer_dirty(bh2, 1);
es->s_free_blocks_count--;
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
sb->s_dirt = 1;
unlock_super (sb);
return j;
}
unsigned long ext2_count_free_blocks (struct super_block * sb)
{
#ifdef EXT2FS_DEBUG
struct ext2_super_block * es;
unsigned long desc_count, bitmap_count, x;
int bitmap_nr;
struct ext2_group_desc * gdp;
int i;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
desc_count = 0;
bitmap_count = 0;
gdp = NULL;
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++) {
gdp = get_group_desc (sb, i, NULL);
desc_count += gdp->bg_free_blocks_count;
bitmap_nr = load_block_bitmap (sb, i);
x = ext2_count_free (sb->u.ext2_sb.s_block_bitmap[bitmap_nr],
sb->s_blocksize);
printk ("group %d: stored = %d, counted = %lu\n",
i, gdp->bg_free_blocks_count, x);
bitmap_count += x;
}
printk("ext2_count_free_blocks: stored = %lu, computed = %lu, %lu\n",
es->s_free_blocks_count, desc_count, bitmap_count);
unlock_super (sb);
return bitmap_count;
#else
return sb->u.ext2_sb.s_es->s_free_blocks_count;
#endif
}
static inline int block_in_use (unsigned long block,
struct super_block * sb,
unsigned char * map)
{
return test_bit ((block - sb->u.ext2_sb.s_es->s_first_data_block) %
EXT2_BLOCKS_PER_GROUP(sb), map);
}
void ext2_check_blocks_bitmap (struct super_block * sb)
{
struct buffer_head * bh;
struct ext2_super_block * es;
unsigned long desc_count, bitmap_count, x;
unsigned long desc_blocks;
int bitmap_nr;
struct ext2_group_desc * gdp;
int i, j;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
desc_count = 0;
bitmap_count = 0;
gdp = NULL;
desc_blocks = (sb->u.ext2_sb.s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
EXT2_DESC_PER_BLOCK(sb);
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++) {
gdp = get_group_desc (sb, i, NULL);
desc_count += gdp->bg_free_blocks_count;
bitmap_nr = load_block_bitmap (sb, i);
bh = sb->u.ext2_sb.s_block_bitmap[bitmap_nr];
if (!test_bit (0, bh->b_data))
ext2_error (sb, "ext2_check_blocks_bitmap",
"Superblock in group %d is marked free", i);
for (j = 0; j < desc_blocks; j++)
if (!test_bit (j + 1, bh->b_data))
ext2_error (sb, "ext2_check_blocks_bitmap",
"Descriptor block #%d in group "
"%d is marked free", j, i);
if (!block_in_use (gdp->bg_block_bitmap, sb, bh->b_data))
ext2_error (sb, "ext2_check_blocks_bitmap",
"Block bitmap for group %d is marked free",
i);
if (!block_in_use (gdp->bg_inode_bitmap, sb, bh->b_data))
ext2_error (sb, "ext2_check_blocks_bitmap",
"Inode bitmap for group %d is marked free",
i);
for (j = 0; j < sb->u.ext2_sb.s_itb_per_group; j++)
if (!block_in_use (gdp->bg_inode_table + j, sb, bh->b_data))
ext2_error (sb, "ext2_check_blocks_bitmap",
"Block #%d of the inode table in "
"group %d is marked free", j, i);
x = ext2_count_free (bh, sb->s_blocksize);
if (gdp->bg_free_blocks_count != x)
ext2_error (sb, "ext2_check_blocks_bitmap",
"Wrong free blocks count for group %d, "
"stored = %d, counted = %lu", i,
gdp->bg_free_blocks_count, x);
bitmap_count += x;
}
if (es->s_free_blocks_count != bitmap_count)
ext2_error (sb, "ext2_check_blocks_bitmap",
"Wrong free blocks count in super block, "
"stored = %lu, counted = %lu",
(unsigned long) es->s_free_blocks_count, bitmap_count);
unlock_super (sb);
}

View file

@ -0,0 +1,555 @@
/*
* linux/fs/ext2/ialloc.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* BSD ufs-inspired inode and directory allocation by
* Stephen Tweedie (sct@dcs.ed.ac.uk), 1993
*/
/*
* ialloc.c contains the inodes allocation and deallocation routines
*/
/*
* The free inodes are managed by bitmaps. A file system contains several
* blocks groups. Each group contains 1 bitmap block for blocks, 1 bitmap
* block for inodes, N blocks for the inode table and data blocks.
*
* The file system contains group descriptors which are located after the
* super block. Each descriptor contains the number of the bitmap block and
* the free blocks count in the block. The descriptors are loaded in memory
* when a file system is mounted (see ext2_read_super).
*/
#include <linux/fs.h>
#include <linux/ext2_fs.h>
#include <linux/sched.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/locks.h>
#include <asm/bitops.h>
static struct ext2_group_desc * get_group_desc (struct super_block * sb,
unsigned int block_group,
struct buffer_head ** bh)
{
unsigned long group_desc;
unsigned long desc;
struct ext2_group_desc * gdp;
if (block_group >= sb->u.ext2_sb.s_groups_count)
ext2_panic (sb, "get_group_desc",
"block_group >= groups_count - "
"block_group = %d, groups_count = %lu",
block_group, sb->u.ext2_sb.s_groups_count);
group_desc = block_group / EXT2_DESC_PER_BLOCK(sb);
desc = block_group % EXT2_DESC_PER_BLOCK(sb);
if (!sb->u.ext2_sb.s_group_desc[group_desc])
ext2_panic (sb, "get_group_desc",
"Group descriptor not loaded - "
"block_group = %d, group_desc = %lu, desc = %lu",
block_group, group_desc, desc);
gdp = (struct ext2_group_desc *)
sb->u.ext2_sb.s_group_desc[group_desc]->b_data;
if (bh)
*bh = sb->u.ext2_sb.s_group_desc[group_desc];
return gdp + desc;
}
static void read_inode_bitmap (struct super_block * sb,
unsigned long block_group,
unsigned int bitmap_nr)
{
struct ext2_group_desc * gdp;
struct buffer_head * bh;
gdp = get_group_desc (sb, block_group, NULL);
bh = bread (sb->s_dev, gdp->bg_inode_bitmap, sb->s_blocksize);
if (!bh)
ext2_panic (sb, "read_inode_bitmap",
"Cannot read inode bitmap - "
"block_group = %lu, inode_bitmap = %lu",
block_group, (unsigned long) gdp->bg_inode_bitmap);
sb->u.ext2_sb.s_inode_bitmap_number[bitmap_nr] = block_group;
sb->u.ext2_sb.s_inode_bitmap[bitmap_nr] = bh;
}
/*
* load_inode_bitmap loads the inode bitmap for a blocks group
*
* It maintains a cache for the last bitmaps loaded. This cache is managed
* with a LRU algorithm.
*
* Notes:
* 1/ There is one cache per mounted file system.
* 2/ If the file system contains less than EXT2_MAX_GROUP_LOADED groups,
* this function reads the bitmap without maintaining a LRU cache.
*/
static int load_inode_bitmap (struct super_block * sb,
unsigned int block_group)
{
int i, j;
unsigned long inode_bitmap_number;
struct buffer_head * inode_bitmap;
if (block_group >= sb->u.ext2_sb.s_groups_count)
ext2_panic (sb, "load_inode_bitmap",
"block_group >= groups_count - "
"block_group = %d, groups_count = %lu",
block_group, sb->u.ext2_sb.s_groups_count);
if (sb->u.ext2_sb.s_loaded_inode_bitmaps > 0 &&
sb->u.ext2_sb.s_inode_bitmap_number[0] == block_group)
return 0;
if (sb->u.ext2_sb.s_groups_count <= EXT2_MAX_GROUP_LOADED) {
if (sb->u.ext2_sb.s_inode_bitmap[block_group]) {
if (sb->u.ext2_sb.s_inode_bitmap_number[block_group] != block_group)
ext2_panic (sb, "load_inode_bitmap",
"block_group != inode_bitmap_number");
else
return block_group;
} else {
read_inode_bitmap (sb, block_group, block_group);
return block_group;
}
}
for (i = 0; i < sb->u.ext2_sb.s_loaded_inode_bitmaps &&
sb->u.ext2_sb.s_inode_bitmap_number[i] != block_group;
i++)
;
if (i < sb->u.ext2_sb.s_loaded_inode_bitmaps &&
sb->u.ext2_sb.s_inode_bitmap_number[i] == block_group) {
inode_bitmap_number = sb->u.ext2_sb.s_inode_bitmap_number[i];
inode_bitmap = sb->u.ext2_sb.s_inode_bitmap[i];
for (j = i; j > 0; j--) {
sb->u.ext2_sb.s_inode_bitmap_number[j] =
sb->u.ext2_sb.s_inode_bitmap_number[j - 1];
sb->u.ext2_sb.s_inode_bitmap[j] =
sb->u.ext2_sb.s_inode_bitmap[j - 1];
}
sb->u.ext2_sb.s_inode_bitmap_number[0] = inode_bitmap_number;
sb->u.ext2_sb.s_inode_bitmap[0] = inode_bitmap;
} else {
if (sb->u.ext2_sb.s_loaded_inode_bitmaps < EXT2_MAX_GROUP_LOADED)
sb->u.ext2_sb.s_loaded_inode_bitmaps++;
else
brelse (sb->u.ext2_sb.s_inode_bitmap[EXT2_MAX_GROUP_LOADED - 1]);
for (j = sb->u.ext2_sb.s_loaded_inode_bitmaps - 1; j > 0; j--) {
sb->u.ext2_sb.s_inode_bitmap_number[j] =
sb->u.ext2_sb.s_inode_bitmap_number[j - 1];
sb->u.ext2_sb.s_inode_bitmap[j] =
sb->u.ext2_sb.s_inode_bitmap[j - 1];
}
read_inode_bitmap (sb, block_group, 0);
}
return 0;
}
/*
* This function sets the deletion time for the inode
*
* This may be used one day by an 'undelete' program
*/
static void set_inode_dtime (struct inode * inode,
struct ext2_group_desc * gdp)
{
unsigned long inode_block;
struct buffer_head * bh;
struct ext2_inode * raw_inode;
inode_block = gdp->bg_inode_table + (((inode->i_ino - 1) %
EXT2_INODES_PER_GROUP(inode->i_sb)) /
EXT2_INODES_PER_BLOCK(inode->i_sb));
bh = bread (inode->i_sb->s_dev, inode_block, inode->i_sb->s_blocksize);
if (!bh)
ext2_panic (inode->i_sb, "set_inode_dtime",
"Cannot load inode table block - "
"inode=%lu, inode_block=%lu",
inode->i_ino, inode_block);
raw_inode = ((struct ext2_inode *) bh->b_data) +
(((inode->i_ino - 1) %
EXT2_INODES_PER_GROUP(inode->i_sb)) %
EXT2_INODES_PER_BLOCK(inode->i_sb));
raw_inode->i_links_count = 0;
raw_inode->i_dtime = CURRENT_TIME;
mark_buffer_dirty(bh, 1);
if (IS_SYNC(inode)) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
brelse (bh);
}
void ext2_free_inode (struct inode * inode)
{
struct super_block * sb;
struct buffer_head * bh;
struct buffer_head * bh2;
unsigned long block_group;
unsigned long bit;
int bitmap_nr;
struct ext2_group_desc * gdp;
struct ext2_super_block * es;
if (!inode)
return;
if (!inode->i_dev) {
printk ("ext2_free_inode: inode has no device\n");
return;
}
if (inode->i_count > 1) {
printk ("ext2_free_inode: inode has count=%d\n",
inode->i_count);
return;
}
if (inode->i_nlink) {
printk ("ext2_free_inode: inode has nlink=%d\n",
inode->i_nlink);
return;
}
if (!inode->i_sb) {
printk("ext2_free_inode: inode on nonexistent device\n");
return;
}
ext2_debug ("freeing inode %lu\n", inode->i_ino);
sb = inode->i_sb;
lock_super (sb);
if (inode->i_ino < EXT2_FIRST_INO ||
inode->i_ino > sb->u.ext2_sb.s_es->s_inodes_count) {
ext2_error (sb, "free_inode",
"reserved inode or nonexistent inode");
unlock_super (sb);
return;
}
es = sb->u.ext2_sb.s_es;
block_group = (inode->i_ino - 1) / EXT2_INODES_PER_GROUP(sb);
bit = (inode->i_ino - 1) % EXT2_INODES_PER_GROUP(sb);
bitmap_nr = load_inode_bitmap (sb, block_group);
bh = sb->u.ext2_sb.s_inode_bitmap[bitmap_nr];
if (!clear_bit (bit, bh->b_data))
ext2_warning (sb, "ext2_free_inode",
"bit already cleared for inode %lu", inode->i_ino);
else {
gdp = get_group_desc (sb, block_group, &bh2);
gdp->bg_free_inodes_count++;
if (S_ISDIR(inode->i_mode))
gdp->bg_used_dirs_count--;
mark_buffer_dirty(bh2, 1);
es->s_free_inodes_count++;
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
set_inode_dtime (inode, gdp);
}
mark_buffer_dirty(bh, 1);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
sb->s_dirt = 1;
clear_inode (inode);
unlock_super (sb);
}
/*
* This function increments the inode version number
*
* This may be used one day by the NFS server
*/
static void inc_inode_version (struct inode * inode,
struct ext2_group_desc *gdp,
int mode)
{
unsigned long inode_block;
struct buffer_head * bh;
struct ext2_inode * raw_inode;
inode_block = gdp->bg_inode_table + (((inode->i_ino - 1) %
EXT2_INODES_PER_GROUP(inode->i_sb)) /
EXT2_INODES_PER_BLOCK(inode->i_sb));
bh = bread (inode->i_sb->s_dev, inode_block, inode->i_sb->s_blocksize);
if (!bh) {
ext2_error (inode->i_sb, "inc_inode_version",
"Cannot load inode table block - "
"inode=%lu, inode_block=%lu\n",
inode->i_ino, inode_block);
inode->u.ext2_i.i_version = 1;
return;
}
raw_inode = ((struct ext2_inode *) bh->b_data) +
(((inode->i_ino - 1) %
EXT2_INODES_PER_GROUP(inode->i_sb)) %
EXT2_INODES_PER_BLOCK(inode->i_sb));
raw_inode->i_version++;
inode->u.ext2_i.i_version = raw_inode->i_version;
mark_buffer_dirty(bh, 1);
brelse (bh);
}
/*
* There are two policies for allocating an inode. If the new inode is
* a directory, then a forward search is made for a block group with both
* free space and a low directory-to-inode ratio; if that fails, then of
* the groups with above-average free space, that group with the fewest
* directories already is chosen.
*
* For other inodes, search forward from the parent directory\'s block
* group to find a free inode.
*/
struct inode * ext2_new_inode (const struct inode * dir, int mode)
{
struct super_block * sb;
struct buffer_head * bh;
struct buffer_head * bh2;
int i, j, avefreei;
struct inode * inode;
int bitmap_nr;
struct ext2_group_desc * gdp;
struct ext2_group_desc * tmp;
struct ext2_super_block * es;
if (!dir || !(inode = get_empty_inode ()))
return NULL;
sb = dir->i_sb;
inode->i_sb = sb;
inode->i_flags = sb->s_flags;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
repeat:
gdp = NULL; i=0;
if (S_ISDIR(mode)) {
avefreei = es->s_free_inodes_count /
sb->u.ext2_sb.s_groups_count;
/* I am not yet convinced that this next bit is necessary.
i = dir->u.ext2_i.i_block_group;
for (j = 0; j < sb->u.ext2_sb.s_groups_count; j++) {
tmp = get_group_desc (sb, i, &bh2);
if ((tmp->bg_used_dirs_count << 8) <
tmp->bg_free_inodes_count) {
gdp = tmp;
break;
}
else
i = ++i % sb->u.ext2_sb.s_groups_count;
}
*/
if (!gdp) {
for (j = 0; j < sb->u.ext2_sb.s_groups_count; j++) {
tmp = get_group_desc (sb, j, &bh2);
if (tmp->bg_free_inodes_count &&
tmp->bg_free_inodes_count >= avefreei) {
if (!gdp ||
(tmp->bg_free_blocks_count >
gdp->bg_free_blocks_count)) {
i = j;
gdp = tmp;
}
}
}
}
}
else
{
/*
* Try to place the inode in its parent directory
*/
i = dir->u.ext2_i.i_block_group;
tmp = get_group_desc (sb, i, &bh2);
if (tmp->bg_free_inodes_count)
gdp = tmp;
else
{
/*
* Use a quadratic hash to find a group with a
* free inode
*/
for (j = 1; j < sb->u.ext2_sb.s_groups_count; j <<= 1) {
i += j;
if (i >= sb->u.ext2_sb.s_groups_count)
i -= sb->u.ext2_sb.s_groups_count;
tmp = get_group_desc (sb, i, &bh2);
if (tmp->bg_free_inodes_count) {
gdp = tmp;
break;
}
}
}
if (!gdp) {
/*
* That failed: try linear search for a free inode
*/
i = dir->u.ext2_i.i_block_group + 1;
for (j = 2; j < sb->u.ext2_sb.s_groups_count; j++) {
if (++i >= sb->u.ext2_sb.s_groups_count)
i = 0;
tmp = get_group_desc (sb, i, &bh2);
if (tmp->bg_free_inodes_count) {
gdp = tmp;
break;
}
}
}
}
if (!gdp) {
unlock_super (sb);
iput(inode);
return NULL;
}
bitmap_nr = load_inode_bitmap (sb, i);
bh = sb->u.ext2_sb.s_inode_bitmap[bitmap_nr];
if ((j = find_first_zero_bit ((unsigned long *) bh->b_data,
EXT2_INODES_PER_GROUP(sb))) <
EXT2_INODES_PER_GROUP(sb)) {
if (set_bit (j, bh->b_data)) {
ext2_warning (sb, "ext2_new_inode",
"bit already set for inode %d", j);
goto repeat;
}
mark_buffer_dirty(bh, 1);
if (sb->s_flags & MS_SYNCHRONOUS) {
ll_rw_block (WRITE, 1, &bh);
wait_on_buffer (bh);
}
} else {
if (gdp->bg_free_inodes_count != 0) {
ext2_error (sb, "ext2_new_inode",
"Free inodes count corrupted in group %d",
i);
unlock_super (sb);
iput (inode);
return NULL;
}
goto repeat;
}
j += i * EXT2_INODES_PER_GROUP(sb) + 1;
if (j < EXT2_FIRST_INO || j > es->s_inodes_count) {
ext2_error (sb, "ext2_new_inode",
"reserved inode or inode > inodes count - "
"block_group = %d,inode=%d", i, j);
unlock_super (sb);
iput (inode);
return NULL;
}
gdp->bg_free_inodes_count--;
if (S_ISDIR(mode))
gdp->bg_used_dirs_count++;
mark_buffer_dirty(bh2, 1);
es->s_free_inodes_count--;
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
sb->s_dirt = 1;
inode->i_mode = mode;
inode->i_sb = sb;
inode->i_count = 1;
inode->i_nlink = 1;
inode->i_dev = sb->s_dev;
inode->i_uid = current->fsuid;
if (test_opt (sb, GRPID))
inode->i_gid = dir->i_gid;
else if (dir->i_mode & S_ISGID) {
inode->i_gid = dir->i_gid;
if (S_ISDIR(mode))
mode |= S_ISGID;
} else
inode->i_gid = current->fsgid;
inode->i_dirt = 1;
inode->i_ino = j;
inode->i_blksize = sb->s_blocksize;
inode->i_blocks = 0;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->u.ext2_i.i_flags = dir->u.ext2_i.i_flags;
if (S_ISLNK(mode))
inode->u.ext2_i.i_flags &= ~(EXT2_IMMUTABLE_FL | EXT2_APPEND_FL);
inode->u.ext2_i.i_faddr = 0;
inode->u.ext2_i.i_frag_no = 0;
inode->u.ext2_i.i_frag_size = 0;
inode->u.ext2_i.i_file_acl = 0;
inode->u.ext2_i.i_dir_acl = 0;
inode->u.ext2_i.i_dtime = 0;
inode->u.ext2_i.i_block_group = i;
inode->i_op = NULL;
if (inode->u.ext2_i.i_flags & EXT2_SYNC_FL)
inode->i_flags |= MS_SYNCHRONOUS;
insert_inode_hash(inode);
inc_inode_version (inode, gdp, mode);
ext2_debug ("allocating inode %lu\n", inode->i_ino);
unlock_super (sb);
return inode;
}
unsigned long ext2_count_free_inodes (struct super_block * sb)
{
#ifdef EXT2FS_DEBUG
struct ext2_super_block * es;
unsigned long desc_count, bitmap_count, x;
int bitmap_nr;
struct ext2_group_desc * gdp;
int i;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
desc_count = 0;
bitmap_count = 0;
gdp = NULL;
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++) {
gdp = get_group_desc (sb, i, NULL);
desc_count += gdp->bg_free_inodes_count;
bitmap_nr = load_inode_bitmap (sb, i);
x = ext2_count_free (sb->u.ext2_sb.s_inode_bitmap[bitmap_nr],
EXT2_INODES_PER_GROUP(sb) / 8);
printk ("group %d: stored = %d, counted = %lu\n",
i, gdp->bg_free_inodes_count, x);
bitmap_count += x;
}
printk("ext2_count_free_inodes: stored = %lu, computed = %lu, %lu\n",
es->s_free_inodes_count, desc_count, bitmap_count);
unlock_super (sb);
return desc_count;
#else
return sb->u.ext2_sb.s_es->s_free_inodes_count;
#endif
}
void ext2_check_inodes_bitmap (struct super_block * sb)
{
struct ext2_super_block * es;
unsigned long desc_count, bitmap_count, x;
int bitmap_nr;
struct ext2_group_desc * gdp;
int i;
lock_super (sb);
es = sb->u.ext2_sb.s_es;
desc_count = 0;
bitmap_count = 0;
gdp = NULL;
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++) {
gdp = get_group_desc (sb, i, NULL);
desc_count += gdp->bg_free_inodes_count;
bitmap_nr = load_inode_bitmap (sb, i);
x = ext2_count_free (sb->u.ext2_sb.s_inode_bitmap[bitmap_nr],
EXT2_INODES_PER_GROUP(sb) / 8);
if (gdp->bg_free_inodes_count != x)
ext2_error (sb, "ext2_check_inodes_bitmap",
"Wrong free inodes count in group %d, "
"stored = %d, counted = %lu", i,
gdp->bg_free_inodes_count, x);
bitmap_count += x;
}
if (es->s_free_inodes_count != bitmap_count)
ext2_error (sb, "ext2_check_inodes_bitmap",
"Wrong free inodes count in super block, "
"stored = %lu, counted = %lu",
(unsigned long) es->s_free_inodes_count, bitmap_count);
unlock_super (sb);
}

780
sys/gnu/ext2fs/ext2_super.c Normal file
View file

@ -0,0 +1,780 @@
/*
* linux/fs/ext2/super.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/fs/minix/inode.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
#include <stdarg.h>
#include <asm/segment.h>
#include <asm/system.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/ext2_fs.h>
#include <linux/malloc.h>
#include <linux/sched.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/locks.h>
static char error_buf[1024];
void ext2_error (struct super_block * sb, const char * function,
const char * fmt, ...)
{
va_list args;
if (!(sb->s_flags & MS_RDONLY)) {
sb->u.ext2_sb.s_mount_state |= EXT2_ERROR_FS;
sb->u.ext2_sb.s_es->s_state |= EXT2_ERROR_FS;
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
sb->s_dirt = 1;
}
va_start (args, fmt);
vsprintf (error_buf, fmt, args);
va_end (args);
if (test_opt (sb, ERRORS_PANIC) ||
(sb->u.ext2_sb.s_es->s_errors == EXT2_ERRORS_PANIC &&
!test_opt (sb, ERRORS_CONT) && !test_opt (sb, ERRORS_RO)))
panic ("EXT2-fs panic (device %d/%d): %s: %s\n",
MAJOR(sb->s_dev), MINOR(sb->s_dev), function, error_buf);
printk (KERN_CRIT "EXT2-fs error (device %d/%d): %s: %s\n",
MAJOR(sb->s_dev), MINOR(sb->s_dev), function, error_buf);
if (test_opt (sb, ERRORS_RO) ||
(sb->u.ext2_sb.s_es->s_errors == EXT2_ERRORS_RO &&
!test_opt (sb, ERRORS_CONT) && !test_opt (sb, ERRORS_PANIC))) {
printk ("Remounting filesystem read-only\n");
sb->s_flags |= MS_RDONLY;
}
}
NORET_TYPE void ext2_panic (struct super_block * sb, const char * function,
const char * fmt, ...)
{
va_list args;
if (!(sb->s_flags & MS_RDONLY)) {
sb->u.ext2_sb.s_mount_state |= EXT2_ERROR_FS;
sb->u.ext2_sb.s_es->s_state |= EXT2_ERROR_FS;
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
sb->s_dirt = 1;
}
va_start (args, fmt);
vsprintf (error_buf, fmt, args);
va_end (args);
panic ("EXT2-fs panic (device %d/%d): %s: %s\n",
MAJOR(sb->s_dev), MINOR(sb->s_dev), function, error_buf);
}
void ext2_warning (struct super_block * sb, const char * function,
const char * fmt, ...)
{
va_list args;
va_start (args, fmt);
vsprintf (error_buf, fmt, args);
va_end (args);
printk (KERN_WARNING "EXT2-fs warning (device %d/%d): %s: %s\n",
MAJOR(sb->s_dev), MINOR(sb->s_dev), function, error_buf);
}
void ext2_put_super (struct super_block * sb)
{
int db_count;
int i;
lock_super (sb);
if (!(sb->s_flags & MS_RDONLY)) {
sb->u.ext2_sb.s_es->s_state = sb->u.ext2_sb.s_mount_state;
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
}
sb->s_dev = 0;
db_count = sb->u.ext2_sb.s_db_per_group;
for (i = 0; i < db_count; i++)
if (sb->u.ext2_sb.s_group_desc[i])
brelse (sb->u.ext2_sb.s_group_desc[i]);
kfree_s (sb->u.ext2_sb.s_group_desc,
db_count * sizeof (struct buffer_head *));
for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++)
if (sb->u.ext2_sb.s_inode_bitmap[i])
brelse (sb->u.ext2_sb.s_inode_bitmap[i]);
for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++)
if (sb->u.ext2_sb.s_block_bitmap[i])
brelse (sb->u.ext2_sb.s_block_bitmap[i]);
brelse (sb->u.ext2_sb.s_sbh);
unlock_super (sb);
return;
}
static struct super_operations ext2_sops = {
ext2_read_inode,
NULL,
ext2_write_inode,
ext2_put_inode,
ext2_put_super,
ext2_write_super,
ext2_statfs,
ext2_remount
};
#ifdef EXT2FS_PRE_02B_COMPAT
static int convert_pre_02b_fs (struct super_block * sb,
struct buffer_head * bh)
{
struct ext2_super_block * es;
struct ext2_old_group_desc old_group_desc [BLOCK_SIZE / sizeof (struct ext2_old_group_desc)];
struct ext2_group_desc * gdp;
struct buffer_head * bh2;
int groups_count;
int i;
es = (struct ext2_super_block *) bh->b_data;
bh2 = bread (sb->s_dev, 2, BLOCK_SIZE);
if (!bh2) {
printk ("Cannot read descriptor blocks while converting !\n");
return 0;
}
memcpy (old_group_desc, bh2->b_data, BLOCK_SIZE);
groups_count = (sb->u.ext2_sb.s_blocks_count -
sb->u.ext2_sb.s_first_data_block +
(EXT2_BLOCK_SIZE(sb) * 8) - 1) /
(EXT2_BLOCK_SIZE(sb) * 8);
memset (bh2->b_data, 0, BLOCK_SIZE);
gdp = (struct ext2_group_desc *) bh2->b_data;
for (i = 0; i < groups_count; i++) {
gdp[i].bg_block_bitmap = old_group_desc[i].bg_block_bitmap;
gdp[i].bg_inode_bitmap = old_group_desc[i].bg_inode_bitmap;
gdp[i].bg_inode_table = old_group_desc[i].bg_inode_table;
gdp[i].bg_free_blocks_count = old_group_desc[i].bg_free_blocks_count;
gdp[i].bg_free_inodes_count = old_group_desc[i].bg_free_inodes_count;
}
mark_buffer_dirty(bh2, 1);
brelse (bh2);
es->s_magic = EXT2_SUPER_MAGIC;
mark_buffer_dirty(bh, 1);
sb->s_magic = EXT2_SUPER_MAGIC;
return 1;
}
#endif
/*
* This function has been shamelessly adapted from the msdos fs
*/
static int parse_options (char * options, unsigned long * sb_block,
unsigned short *resuid, unsigned short * resgid,
unsigned long * mount_options)
{
char * this_char;
char * value;
if (!options)
return 1;
for (this_char = strtok (options, ",");
this_char != NULL;
this_char = strtok (NULL, ",")) {
if ((value = strchr (this_char, '=')) != NULL)
*value++ = 0;
if (!strcmp (this_char, "bsddf"))
clear_opt (*mount_options, MINIX_DF);
else if (!strcmp (this_char, "check")) {
if (!value || !*value)
set_opt (*mount_options, CHECK_NORMAL);
else if (!strcmp (value, "none")) {
clear_opt (*mount_options, CHECK_NORMAL);
clear_opt (*mount_options, CHECK_STRICT);
}
else if (strcmp (value, "normal"))
set_opt (*mount_options, CHECK_NORMAL);
else if (strcmp (value, "strict")) {
set_opt (*mount_options, CHECK_NORMAL);
set_opt (*mount_options, CHECK_STRICT);
}
else {
printk ("EXT2-fs: Invalid check option: %s\n",
value);
return 0;
}
}
else if (!strcmp (this_char, "debug"))
set_opt (*mount_options, DEBUG);
else if (!strcmp (this_char, "errors")) {
if (!value || !*value) {
printk ("EXT2-fs: the errors option requires "
"an argument");
return 0;
}
if (!strcmp (value, "continue")) {
clear_opt (*mount_options, ERRORS_RO);
clear_opt (*mount_options, ERRORS_PANIC);
set_opt (*mount_options, ERRORS_CONT);
}
else if (!strcmp (value, "remount-ro")) {
clear_opt (*mount_options, ERRORS_CONT);
clear_opt (*mount_options, ERRORS_PANIC);
set_opt (*mount_options, ERRORS_RO);
}
else if (!strcmp (value, "panic")) {
clear_opt (*mount_options, ERRORS_CONT);
clear_opt (*mount_options, ERRORS_RO);
set_opt (*mount_options, ERRORS_PANIC);
}
else {
printk ("EXT2-fs: Invalid errors option: %s\n",
value);
return 0;
}
}
else if (!strcmp (this_char, "grpid") ||
!strcmp (this_char, "bsdgroups"))
set_opt (*mount_options, GRPID);
else if (!strcmp (this_char, "minixdf"))
set_opt (*mount_options, MINIX_DF);
else if (!strcmp (this_char, "nocheck")) {
clear_opt (*mount_options, CHECK_NORMAL);
clear_opt (*mount_options, CHECK_STRICT);
}
else if (!strcmp (this_char, "nogrpid") ||
!strcmp (this_char, "sysvgroups"))
clear_opt (*mount_options, GRPID);
else if (!strcmp (this_char, "resgid")) {
if (!value || !*value) {
printk ("EXT2-fs: the resgid option requires "
"an argument");
return 0;
}
*resgid = simple_strtoul (value, &value, 0);
if (*value) {
printk ("EXT2-fs: Invalid resgid option: %s\n",
value);
return 0;
}
}
else if (!strcmp (this_char, "resuid")) {
if (!value || !*value) {
printk ("EXT2-fs: the resuid option requires "
"an argument");
return 0;
}
*resuid = simple_strtoul (value, &value, 0);
if (*value) {
printk ("EXT2-fs: Invalid resuid option: %s\n",
value);
return 0;
}
}
else if (!strcmp (this_char, "sb")) {
if (!value || !*value) {
printk ("EXT2-fs: the sb option requires "
"an argument");
return 0;
}
*sb_block = simple_strtoul (value, &value, 0);
if (*value) {
printk ("EXT2-fs: Invalid sb option: %s\n",
value);
return 0;
}
}
else {
printk ("EXT2-fs: Unrecognized mount option %s\n", this_char);
return 0;
}
}
return 1;
}
static void ext2_setup_super (struct super_block * sb,
struct ext2_super_block * es)
{
if (es->s_rev_level > EXT2_CURRENT_REV) {
printk ("EXT2-fs warning: revision level too high, "
"forcing read/only mode\n");
sb->s_flags |= MS_RDONLY;
}
if (!(sb->s_flags & MS_RDONLY)) {
if (!(sb->u.ext2_sb.s_mount_state & EXT2_VALID_FS))
printk ("EXT2-fs warning: mounting unchecked fs, "
"running e2fsck is recommended\n");
else if ((sb->u.ext2_sb.s_mount_state & EXT2_ERROR_FS))
printk ("EXT2-fs warning: mounting fs with errors, "
"running e2fsck is recommended\n");
else if (es->s_max_mnt_count >= 0 &&
es->s_mnt_count >= (unsigned short) es->s_max_mnt_count)
printk ("EXT2-fs warning: maximal mount count reached, "
"running e2fsck is recommended\n");
else if (es->s_checkinterval &&
(es->s_lastcheck + es->s_checkinterval <= CURRENT_TIME))
printk ("EXT2-fs warning: checktime reached, "
"running e2fsck is recommended\n");
es->s_state &= ~EXT2_VALID_FS;
if (!es->s_max_mnt_count)
es->s_max_mnt_count = EXT2_DFL_MAX_MNT_COUNT;
es->s_mnt_count++;
es->s_mtime = CURRENT_TIME;
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
sb->s_dirt = 1;
if (test_opt (sb, DEBUG))
printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
"bpg=%lu, ipg=%lu, mo=%04lx]\n",
EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
sb->u.ext2_sb.s_frag_size,
sb->u.ext2_sb.s_groups_count,
EXT2_BLOCKS_PER_GROUP(sb),
EXT2_INODES_PER_GROUP(sb),
sb->u.ext2_sb.s_mount_opt);
if (test_opt (sb, CHECK)) {
ext2_check_blocks_bitmap (sb);
ext2_check_inodes_bitmap (sb);
}
}
}
static int ext2_check_descriptors (struct super_block * sb)
{
int i;
int desc_block = 0;
unsigned long block = sb->u.ext2_sb.s_es->s_first_data_block;
struct ext2_group_desc * gdp = NULL;
ext2_debug ("Checking group descriptors");
for (i = 0; i < sb->u.ext2_sb.s_groups_count; i++)
{
if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
gdp = (struct ext2_group_desc *) sb->u.ext2_sb.s_group_desc[desc_block++]->b_data;
if (gdp->bg_block_bitmap < block ||
gdp->bg_block_bitmap >= block + EXT2_BLOCKS_PER_GROUP(sb))
{
ext2_error (sb, "ext2_check_descriptors",
"Block bitmap for group %d"
" not in group (block %lu)!",
i, (unsigned long) gdp->bg_block_bitmap);
return 0;
}
if (gdp->bg_inode_bitmap < block ||
gdp->bg_inode_bitmap >= block + EXT2_BLOCKS_PER_GROUP(sb))
{
ext2_error (sb, "ext2_check_descriptors",
"Inode bitmap for group %d"
" not in group (block %lu)!",
i, (unsigned long) gdp->bg_inode_bitmap);
return 0;
}
if (gdp->bg_inode_table < block ||
gdp->bg_inode_table + sb->u.ext2_sb.s_itb_per_group >=
block + EXT2_BLOCKS_PER_GROUP(sb))
{
ext2_error (sb, "ext2_check_descriptors",
"Inode table for group %d"
" not in group (block %lu)!",
i, (unsigned long) gdp->bg_inode_table);
return 0;
}
block += EXT2_BLOCKS_PER_GROUP(sb);
gdp++;
}
return 1;
}
struct super_block * ext2_read_super (struct super_block * sb, void * data,
int silent)
{
struct buffer_head * bh;
struct ext2_super_block * es;
unsigned long sb_block = 1;
unsigned short resuid = EXT2_DEF_RESUID;
unsigned short resgid = EXT2_DEF_RESGID;
unsigned long logic_sb_block = 1;
int dev = sb->s_dev;
int db_count;
int i, j;
#ifdef EXT2FS_PRE_02B_COMPAT
int fs_converted = 0;
#endif
set_opt (sb->u.ext2_sb.s_mount_opt, CHECK_NORMAL);
if (!parse_options ((char *) data, &sb_block, &resuid, &resgid,
&sb->u.ext2_sb.s_mount_opt)) {
sb->s_dev = 0;
return NULL;
}
lock_super (sb);
set_blocksize (dev, BLOCK_SIZE);
if (!(bh = bread (dev, sb_block, BLOCK_SIZE))) {
sb->s_dev = 0;
unlock_super (sb);
printk ("EXT2-fs: unable to read superblock\n");
return NULL;
}
/*
* Note: s_es must be initialized s_es as soon as possible because
* some ext2 macro-instructions depend on its value
*/
es = (struct ext2_super_block *) bh->b_data;
sb->u.ext2_sb.s_es = es;
sb->s_magic = es->s_magic;
if (sb->s_magic != EXT2_SUPER_MAGIC
#ifdef EXT2FS_PRE_02B_COMPAT
&& sb->s_magic != EXT2_PRE_02B_MAGIC
#endif
) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
if (!silent)
printk ("VFS: Can't find an ext2 filesystem on dev %d/%d.\n",
MAJOR(dev), MINOR(dev));
return NULL;
}
sb->s_blocksize = EXT2_MIN_BLOCK_SIZE << es->s_log_block_size;
sb->s_blocksize_bits = EXT2_BLOCK_SIZE_BITS(sb);
if (sb->s_blocksize != BLOCK_SIZE &&
(sb->s_blocksize == 1024 || sb->s_blocksize == 2048 ||
sb->s_blocksize == 4096)) {
unsigned long offset;
brelse (bh);
set_blocksize (dev, sb->s_blocksize);
logic_sb_block = (sb_block*BLOCK_SIZE) / sb->s_blocksize;
offset = (sb_block*BLOCK_SIZE) % sb->s_blocksize;
bh = bread (dev, logic_sb_block, sb->s_blocksize);
if(!bh)
return NULL;
es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
sb->u.ext2_sb.s_es = es;
if (es->s_magic != EXT2_SUPER_MAGIC) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
printk ("EXT2-fs: Magic mismatch, very weird !\n");
return NULL;
}
}
sb->u.ext2_sb.s_frag_size = EXT2_MIN_FRAG_SIZE <<
es->s_log_frag_size;
if (sb->u.ext2_sb.s_frag_size)
sb->u.ext2_sb.s_frags_per_block = sb->s_blocksize /
sb->u.ext2_sb.s_frag_size;
else
sb->s_magic = 0;
sb->u.ext2_sb.s_blocks_per_group = es->s_blocks_per_group;
sb->u.ext2_sb.s_frags_per_group = es->s_frags_per_group;
sb->u.ext2_sb.s_inodes_per_group = es->s_inodes_per_group;
sb->u.ext2_sb.s_inodes_per_block = sb->s_blocksize /
sizeof (struct ext2_inode);
sb->u.ext2_sb.s_itb_per_group = sb->u.ext2_sb.s_inodes_per_group /
sb->u.ext2_sb.s_inodes_per_block;
sb->u.ext2_sb.s_desc_per_block = sb->s_blocksize /
sizeof (struct ext2_group_desc);
sb->u.ext2_sb.s_sbh = bh;
sb->u.ext2_sb.s_es = es;
if (resuid != EXT2_DEF_RESUID)
sb->u.ext2_sb.s_resuid = resuid;
else
sb->u.ext2_sb.s_resuid = es->s_def_resuid;
if (resgid != EXT2_DEF_RESGID)
sb->u.ext2_sb.s_resgid = resgid;
else
sb->u.ext2_sb.s_resgid = es->s_def_resgid;
sb->u.ext2_sb.s_mount_state = es->s_state;
sb->u.ext2_sb.s_rename_lock = 0;
sb->u.ext2_sb.s_rename_wait = NULL;
#ifdef EXT2FS_PRE_02B_COMPAT
if (sb->s_magic == EXT2_PRE_02B_MAGIC) {
if (es->s_blocks_count > 262144) {
/*
* fs > 256 MB can't be converted
*/
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
printk ("EXT2-fs: trying to mount a pre-0.2b file"
"system which cannot be converted\n");
return NULL;
}
printk ("EXT2-fs: mounting a pre 0.2b file system, "
"will try to convert the structure\n");
if (!(sb->s_flags & MS_RDONLY)) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
printk ("EXT2-fs: cannot convert a read-only fs\n");
return NULL;
}
if (!convert_pre_02b_fs (sb, bh)) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
printk ("EXT2-fs: conversion failed !!!\n");
return NULL;
}
printk ("EXT2-fs: conversion succeeded !!!\n");
fs_converted = 1;
}
#endif
if (sb->s_magic != EXT2_SUPER_MAGIC) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
if (!silent)
printk ("VFS: Can't find an ext2 filesystem on dev %d/%d.\n",
MAJOR(dev), MINOR(dev));
return NULL;
}
if (sb->s_blocksize != bh->b_size) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
if (!silent)
printk ("VFS: Unsupported blocksize on dev 0x%04x.\n",
dev);
return NULL;
}
if (sb->s_blocksize != sb->u.ext2_sb.s_frag_size) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
sb->u.ext2_sb.s_frag_size, sb->s_blocksize);
return NULL;
}
if (sb->u.ext2_sb.s_blocks_per_group > sb->s_blocksize * 8) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
printk ("EXT2-fs: #blocks per group too big: %lu\n",
sb->u.ext2_sb.s_blocks_per_group);
return NULL;
}
if (sb->u.ext2_sb.s_frags_per_group > sb->s_blocksize * 8) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
printk ("EXT2-fs: #fragments per group too big: %lu\n",
sb->u.ext2_sb.s_frags_per_group);
return NULL;
}
if (sb->u.ext2_sb.s_inodes_per_group > sb->s_blocksize * 8) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
printk ("EXT2-fs: #inodes per group too big: %lu\n",
sb->u.ext2_sb.s_inodes_per_group);
return NULL;
}
sb->u.ext2_sb.s_groups_count = (es->s_blocks_count -
es->s_first_data_block +
EXT2_BLOCKS_PER_GROUP(sb) - 1) /
EXT2_BLOCKS_PER_GROUP(sb);
db_count = (sb->u.ext2_sb.s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
EXT2_DESC_PER_BLOCK(sb);
sb->u.ext2_sb.s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
if (sb->u.ext2_sb.s_group_desc == NULL) {
sb->s_dev = 0;
unlock_super (sb);
brelse (bh);
printk ("EXT2-fs: not enough memory\n");
return NULL;
}
for (i = 0; i < db_count; i++) {
sb->u.ext2_sb.s_group_desc[i] = bread (dev, logic_sb_block + i + 1,
sb->s_blocksize);
if (!sb->u.ext2_sb.s_group_desc[i]) {
sb->s_dev = 0;
unlock_super (sb);
for (j = 0; j < i; j++)
brelse (sb->u.ext2_sb.s_group_desc[j]);
kfree_s (sb->u.ext2_sb.s_group_desc,
db_count * sizeof (struct buffer_head *));
brelse (bh);
printk ("EXT2-fs: unable to read group descriptors\n");
return NULL;
}
}
if (!ext2_check_descriptors (sb)) {
sb->s_dev = 0;
unlock_super (sb);
for (j = 0; j < db_count; j++)
brelse (sb->u.ext2_sb.s_group_desc[j]);
kfree_s (sb->u.ext2_sb.s_group_desc,
db_count * sizeof (struct buffer_head *));
brelse (bh);
printk ("EXT2-fs: group descriptors corrupted !\n");
return NULL;
}
for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++) {
sb->u.ext2_sb.s_inode_bitmap_number[i] = 0;
sb->u.ext2_sb.s_inode_bitmap[i] = NULL;
sb->u.ext2_sb.s_block_bitmap_number[i] = 0;
sb->u.ext2_sb.s_block_bitmap[i] = NULL;
}
sb->u.ext2_sb.s_loaded_inode_bitmaps = 0;
sb->u.ext2_sb.s_loaded_block_bitmaps = 0;
sb->u.ext2_sb.s_db_per_group = db_count;
unlock_super (sb);
/*
* set up enough so that it can read an inode
*/
sb->s_dev = dev;
sb->s_op = &ext2_sops;
if (!(sb->s_mounted = iget (sb, EXT2_ROOT_INO))) {
sb->s_dev = 0;
for (i = 0; i < db_count; i++)
if (sb->u.ext2_sb.s_group_desc[i])
brelse (sb->u.ext2_sb.s_group_desc[i]);
kfree_s (sb->u.ext2_sb.s_group_desc,
db_count * sizeof (struct buffer_head *));
brelse (bh);
printk ("EXT2-fs: get root inode failed\n");
return NULL;
}
#ifdef EXT2FS_PRE_02B_COMPAT
if (fs_converted) {
for (i = 0; i < db_count; i++)
mark_buffer_dirty(sb->u.ext2_sb.s_group_desc[i], 1);
sb->s_dirt = 1;
}
#endif
ext2_setup_super (sb, es);
return sb;
}
static void ext2_commit_super (struct super_block * sb,
struct ext2_super_block * es)
{
es->s_wtime = CURRENT_TIME;
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
sb->s_dirt = 0;
}
/*
* In the second extended file system, it is not necessary to
* write the super block since we use a mapping of the
* disk super block in a buffer.
*
* However, this function is still used to set the fs valid
* flags to 0. We need to set this flag to 0 since the fs
* may have been checked while mounted and e2fsck may have
* set s_state to EXT2_VALID_FS after some corrections.
*/
void ext2_write_super (struct super_block * sb)
{
struct ext2_super_block * es;
if (!(sb->s_flags & MS_RDONLY)) {
es = sb->u.ext2_sb.s_es;
ext2_debug ("setting valid to 0\n");
if (es->s_state & EXT2_VALID_FS) {
es->s_state &= ~EXT2_VALID_FS;
es->s_mtime = CURRENT_TIME;
}
ext2_commit_super (sb, es);
}
sb->s_dirt = 0;
}
int ext2_remount (struct super_block * sb, int * flags, char * data)
{
struct ext2_super_block * es;
unsigned short resuid = sb->u.ext2_sb.s_resuid;
unsigned short resgid = sb->u.ext2_sb.s_resgid;
unsigned long new_mount_opt;
unsigned long tmp;
/*
* Allow the "check" option to be passed as a remount option.
*/
set_opt (sb->u.ext2_sb.s_mount_opt, CHECK_NORMAL);
if (!parse_options (data, &tmp, &resuid, &resgid,
&new_mount_opt))
return -EINVAL;
sb->u.ext2_sb.s_mount_opt = new_mount_opt;
sb->u.ext2_sb.s_resuid = resuid;
sb->u.ext2_sb.s_resgid = resgid;
es = sb->u.ext2_sb.s_es;
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
return 0;
if (*flags & MS_RDONLY) {
if (es->s_state & EXT2_VALID_FS ||
!(sb->u.ext2_sb.s_mount_state & EXT2_VALID_FS))
return 0;
/*
* OK, we are remounting a valid rw partition rdonly, so set
* the rdonly flag and then mark the partition as valid again.
*/
es->s_state = sb->u.ext2_sb.s_mount_state;
es->s_mtime = CURRENT_TIME;
mark_buffer_dirty(sb->u.ext2_sb.s_sbh, 1);
sb->s_dirt = 1;
ext2_commit_super (sb, es);
}
else {
/*
* Mounting a RDONLY partition read-write, so reread and
* store the current valid flag. (It may have been changed
* by e2fsck since we originally mounted the partition.)
*/
sb->u.ext2_sb.s_mount_state = es->s_state;
sb->s_flags &= ~MS_RDONLY;
ext2_setup_super (sb, es);
}
return 0;
}
void ext2_statfs (struct super_block * sb, struct statfs * buf)
{
long tmp;
unsigned long overhead;
unsigned long overhead_per_group;
if (test_opt (sb, MINIX_DF))
overhead = 0;
else {
/*
* Compute the overhead (FS structures)
*/
overhead_per_group = 1 /* super block */ +
sb->u.ext2_sb.s_db_per_group /* descriptors */ +
1 /* block bitmap */ +
1 /* inode bitmap */ +
sb->u.ext2_sb.s_itb_per_group /* inode table */;
overhead = sb->u.ext2_sb.s_es->s_first_data_block +
sb->u.ext2_sb.s_groups_count * overhead_per_group;
}
put_fs_long (EXT2_SUPER_MAGIC, &buf->f_type);
put_fs_long (sb->s_blocksize, &buf->f_bsize);
put_fs_long (sb->u.ext2_sb.s_es->s_blocks_count - overhead,
&buf->f_blocks);
tmp = ext2_count_free_blocks (sb);
put_fs_long (tmp, &buf->f_bfree);
if (tmp >= sb->u.ext2_sb.s_es->s_r_blocks_count)
put_fs_long (tmp - sb->u.ext2_sb.s_es->s_r_blocks_count,
&buf->f_bavail);
else
put_fs_long (0, &buf->f_bavail);
put_fs_long (sb->u.ext2_sb.s_es->s_inodes_count, &buf->f_files);
put_fs_long (ext2_count_free_inodes (sb), &buf->f_ffree);
put_fs_long (EXT2_NAME_LEN, &buf->f_namelen);
/* Don't know what value to put in buf->f_fsid */
}