| /* |
| * 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 |
| * |
| * Big-endian to little-endian byte-swapping/bitmaps by |
| * David S. Miller (davem@caip.rutgers.edu), 1995 |
| */ |
| |
| #include <linux/config.h> |
| #include <linux/module.h> |
| #include <linux/string.h> |
| #include <linux/fs.h> |
| #include <linux/ext2_fs.h> |
| #include <linux/slab.h> |
| #include <linux/init.h> |
| #include <linux/locks.h> |
| #include <linux/blkdev.h> |
| #include <asm/uaccess.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 = |
| cpu_to_le16(le16_to_cpu(sb->u.ext2_sb.s_es->s_state) | EXT2_ERROR_FS); |
| mark_buffer_dirty(sb->u.ext2_sb.s_sbh); |
| sb->s_dirt = 1; |
| } |
| va_start (args, fmt); |
| vsprintf (error_buf, fmt, args); |
| va_end (args); |
| if (test_opt (sb, ERRORS_PANIC) || |
| (le16_to_cpu(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 %s): %s: %s\n", |
| bdevname(sb->s_dev), function, error_buf); |
| printk (KERN_CRIT "EXT2-fs error (device %s): %s: %s\n", |
| bdevname(sb->s_dev), function, error_buf); |
| if (test_opt (sb, ERRORS_RO) || |
| (le16_to_cpu(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 = |
| cpu_to_le16(le16_to_cpu(sb->u.ext2_sb.s_es->s_state) | EXT2_ERROR_FS); |
| mark_buffer_dirty(sb->u.ext2_sb.s_sbh); |
| sb->s_dirt = 1; |
| } |
| va_start (args, fmt); |
| vsprintf (error_buf, fmt, args); |
| va_end (args); |
| sb->s_flags |= MS_RDONLY; |
| panic ("EXT2-fs panic (device %s): %s: %s\n", |
| bdevname(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 %s): %s: %s\n", |
| bdevname(sb->s_dev), function, error_buf); |
| } |
| |
| void ext2_update_dynamic_rev(struct super_block *sb) |
| { |
| struct ext2_super_block *es = EXT2_SB(sb)->s_es; |
| |
| if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV) |
| return; |
| |
| ext2_warning(sb, __FUNCTION__, |
| "updating to rev %d because of new feature flag, " |
| "running e2fsck is recommended", |
| EXT2_DYNAMIC_REV); |
| |
| es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO); |
| es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE); |
| es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV); |
| /* leave es->s_feature_*compat flags alone */ |
| /* es->s_uuid will be set by e2fsck if empty */ |
| |
| /* |
| * The rest of the superblock fields should be zero, and if not it |
| * means they are likely already in use, so leave them alone. We |
| * can leave it up to e2fsck to clean up any inconsistencies there. |
| */ |
| } |
| |
| void ext2_put_super (struct super_block * sb) |
| { |
| int db_count; |
| int i; |
| |
| if (!(sb->s_flags & MS_RDONLY)) { |
| sb->u.ext2_sb.s_es->s_state = le16_to_cpu(sb->u.ext2_sb.s_mount_state); |
| mark_buffer_dirty(sb->u.ext2_sb.s_sbh); |
| } |
| db_count = EXT2_SB(sb)->s_gdb_count; |
| 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(sb->u.ext2_sb.s_group_desc); |
| 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); |
| |
| return; |
| } |
| |
| static struct super_operations ext2_sops = { |
| read_inode: ext2_read_inode, |
| write_inode: ext2_write_inode, |
| put_inode: ext2_put_inode, |
| delete_inode: ext2_delete_inode, |
| put_super: ext2_put_super, |
| write_super: ext2_write_super, |
| statfs: ext2_statfs, |
| remount_fs: ext2_remount, |
| }; |
| |
| /* |
| * 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, "nouid32")) { |
| set_opt (*mount_options, NO_UID32); |
| } |
| else if (!strcmp (this_char, "check")) { |
| if (!value || !*value || !strcmp (value, "none")) |
| clear_opt (*mount_options, CHECK); |
| else |
| #ifdef CONFIG_EXT2_CHECK |
| set_opt (*mount_options, CHECK); |
| #else |
| printk("EXT2 Check option not supported\n"); |
| #endif |
| } |
| 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\n"); |
| 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); |
| 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\n"); |
| 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; |
| } |
| } |
| /* Silently ignore the quota options */ |
| else if (!strcmp (this_char, "grpquota") |
| || !strcmp (this_char, "noquota") |
| || !strcmp (this_char, "quota") |
| || !strcmp (this_char, "usrquota")) |
| /* Don't do anything ;-) */ ; |
| else { |
| printk ("EXT2-fs: Unrecognized mount option %s\n", this_char); |
| return 0; |
| } |
| } |
| return 1; |
| } |
| |
| static int ext2_setup_super (struct super_block * sb, |
| struct ext2_super_block * es, |
| int read_only) |
| { |
| int res = 0; |
| if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) { |
| printk ("EXT2-fs warning: revision level too high, " |
| "forcing read-only mode\n"); |
| res = MS_RDONLY; |
| } |
| if (read_only) |
| return res; |
| 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 ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 && |
| le16_to_cpu(es->s_mnt_count) >= |
| (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count)) |
| printk ("EXT2-fs warning: maximal mount count reached, " |
| "running e2fsck is recommended\n"); |
| else if (le32_to_cpu(es->s_checkinterval) && |
| (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= CURRENT_TIME)) |
| printk ("EXT2-fs warning: checktime reached, " |
| "running e2fsck is recommended\n"); |
| es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & ~EXT2_VALID_FS); |
| if (!(__s16) le16_to_cpu(es->s_max_mnt_count)) |
| es->s_max_mnt_count = (__s16) cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT); |
| es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1); |
| es->s_mtime = cpu_to_le32(CURRENT_TIME); |
| mark_buffer_dirty(sb->u.ext2_sb.s_sbh); |
| 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); |
| #ifdef CONFIG_EXT2_CHECK |
| if (test_opt (sb, CHECK)) { |
| ext2_check_blocks_bitmap (sb); |
| ext2_check_inodes_bitmap (sb); |
| } |
| #endif |
| return res; |
| } |
| |
| static int ext2_check_descriptors (struct super_block * sb) |
| { |
| int i; |
| int desc_block = 0; |
| unsigned long block = le32_to_cpu(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 (le32_to_cpu(gdp->bg_block_bitmap) < block || |
| le32_to_cpu(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) le32_to_cpu(gdp->bg_block_bitmap)); |
| return 0; |
| } |
| if (le32_to_cpu(gdp->bg_inode_bitmap) < block || |
| le32_to_cpu(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) le32_to_cpu(gdp->bg_inode_bitmap)); |
| return 0; |
| } |
| if (le32_to_cpu(gdp->bg_inode_table) < block || |
| le32_to_cpu(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) le32_to_cpu(gdp->bg_inode_table)); |
| return 0; |
| } |
| block += EXT2_BLOCKS_PER_GROUP(sb); |
| gdp++; |
| } |
| return 1; |
| } |
| |
| #define log2(n) ffz(~(n)) |
| |
| /* |
| * Maximal file size. There is a direct, and {,double-,triple-}indirect |
| * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks. |
| * We need to be 1 filesystem block less than the 2^32 sector limit. |
| */ |
| static loff_t ext2_max_size(int bits) |
| { |
| loff_t res = EXT2_NDIR_BLOCKS; |
| res += 1LL << (bits-2); |
| res += 1LL << (2*(bits-2)); |
| res += 1LL << (3*(bits-2)); |
| res <<= bits; |
| if (res > (512LL << 32) - (1 << bits)) |
| res = (512LL << 32) - (1 << bits); |
| return res; |
| } |
| |
| 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; |
| unsigned long offset = 0; |
| kdev_t dev = sb->s_dev; |
| int blocksize = BLOCK_SIZE; |
| int db_count; |
| int i, j; |
| |
| /* |
| * See what the current blocksize for the device is, and |
| * use that as the blocksize. Otherwise (or if the blocksize |
| * is smaller than the default) use the default. |
| * This is important for devices that have a hardware |
| * sectorsize that is larger than the default. |
| */ |
| blocksize = get_hardsect_size(dev); |
| if(blocksize < BLOCK_SIZE ) |
| blocksize = BLOCK_SIZE; |
| |
| sb->u.ext2_sb.s_mount_opt = 0; |
| if (!parse_options ((char *) data, &sb_block, &resuid, &resgid, |
| &sb->u.ext2_sb.s_mount_opt)) { |
| return NULL; |
| } |
| |
| if (set_blocksize(dev, blocksize) < 0) { |
| printk ("EXT2-fs: unable to set blocksize %d\n", blocksize); |
| return NULL; |
| } |
| |
| /* |
| * If the superblock doesn't start on a sector boundary, |
| * calculate the offset. FIXME(eric) this doesn't make sense |
| * that we would have to do this. |
| */ |
| if (blocksize != BLOCK_SIZE) { |
| logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; |
| offset = (sb_block*BLOCK_SIZE) % blocksize; |
| } |
| |
| if (!(bh = bread (dev, logic_sb_block, blocksize))) { |
| printk ("EXT2-fs: unable to read superblock\n"); |
| return NULL; |
| } |
| /* |
| * Note: s_es must be initialized as soon as possible because |
| * some ext2 macro-instructions depend on its value |
| */ |
| es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); |
| sb->u.ext2_sb.s_es = es; |
| sb->s_magic = le16_to_cpu(es->s_magic); |
| if (sb->s_magic != EXT2_SUPER_MAGIC) { |
| if (!silent) |
| printk ("VFS: Can't find ext2 filesystem on dev %s.\n", |
| bdevname(dev)); |
| goto failed_mount; |
| } |
| if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV && |
| (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) || |
| EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) || |
| EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U))) |
| printk("EXT2-fs warning: feature flags set on rev 0 fs, " |
| "running e2fsck is recommended\n"); |
| /* |
| * Check feature flags regardless of the revision level, since we |
| * previously didn't change the revision level when setting the flags, |
| * so there is a chance incompat flags are set on a rev 0 filesystem. |
| */ |
| if ((i = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP))) { |
| printk("EXT2-fs: %s: couldn't mount because of " |
| "unsupported optional features (%x).\n", |
| bdevname(dev), i); |
| goto failed_mount; |
| } |
| if (!(sb->s_flags & MS_RDONLY) && |
| (i = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){ |
| printk("EXT2-fs: %s: couldn't mount RDWR because of " |
| "unsupported optional features (%x).\n", |
| bdevname(dev), i); |
| goto failed_mount; |
| } |
| sb->s_blocksize_bits = |
| le32_to_cpu(EXT2_SB(sb)->s_es->s_log_block_size) + 10; |
| sb->s_blocksize = 1 << sb->s_blocksize_bits; |
| |
| sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits); |
| |
| /* If the blocksize doesn't match, re-read the thing.. */ |
| if (sb->s_blocksize != blocksize) { |
| blocksize = sb->s_blocksize; |
| brelse(bh); |
| |
| if (set_blocksize(dev, blocksize) < 0) { |
| printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n"); |
| return NULL; |
| } |
| |
| logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize; |
| offset = (sb_block*BLOCK_SIZE) % blocksize; |
| bh = bread (dev, logic_sb_block, blocksize); |
| if(!bh) { |
| printk("EXT2-fs: Couldn't read superblock on " |
| "2nd try.\n"); |
| goto failed_mount; |
| } |
| es = (struct ext2_super_block *) (((char *)bh->b_data) + offset); |
| sb->u.ext2_sb.s_es = es; |
| if (es->s_magic != le16_to_cpu(EXT2_SUPER_MAGIC)) { |
| printk ("EXT2-fs: Magic mismatch, very weird !\n"); |
| goto failed_mount; |
| } |
| } |
| |
| if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) { |
| sb->u.ext2_sb.s_inode_size = EXT2_GOOD_OLD_INODE_SIZE; |
| sb->u.ext2_sb.s_first_ino = EXT2_GOOD_OLD_FIRST_INO; |
| } else { |
| sb->u.ext2_sb.s_inode_size = le16_to_cpu(es->s_inode_size); |
| sb->u.ext2_sb.s_first_ino = le32_to_cpu(es->s_first_ino); |
| if (sb->u.ext2_sb.s_inode_size != EXT2_GOOD_OLD_INODE_SIZE) { |
| printk ("EXT2-fs: unsupported inode size: %d\n", |
| sb->u.ext2_sb.s_inode_size); |
| goto failed_mount; |
| } |
| } |
| sb->u.ext2_sb.s_frag_size = EXT2_MIN_FRAG_SIZE << |
| le32_to_cpu(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 = le32_to_cpu(es->s_blocks_per_group); |
| sb->u.ext2_sb.s_frags_per_group = le32_to_cpu(es->s_frags_per_group); |
| sb->u.ext2_sb.s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group); |
| sb->u.ext2_sb.s_inodes_per_block = sb->s_blocksize / |
| EXT2_INODE_SIZE(sb); |
| 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; |
| if (resuid != EXT2_DEF_RESUID) |
| sb->u.ext2_sb.s_resuid = resuid; |
| else |
| sb->u.ext2_sb.s_resuid = le16_to_cpu(es->s_def_resuid); |
| if (resgid != EXT2_DEF_RESGID) |
| sb->u.ext2_sb.s_resgid = resgid; |
| else |
| sb->u.ext2_sb.s_resgid = le16_to_cpu(es->s_def_resgid); |
| sb->u.ext2_sb.s_mount_state = le16_to_cpu(es->s_state); |
| sb->u.ext2_sb.s_addr_per_block_bits = |
| log2 (EXT2_ADDR_PER_BLOCK(sb)); |
| sb->u.ext2_sb.s_desc_per_block_bits = |
| log2 (EXT2_DESC_PER_BLOCK(sb)); |
| if (sb->s_magic != EXT2_SUPER_MAGIC) { |
| if (!silent) |
| printk ("VFS: Can't find an ext2 filesystem on dev " |
| "%s.\n", |
| bdevname(dev)); |
| goto failed_mount; |
| } |
| if (sb->s_blocksize != bh->b_size) { |
| if (!silent) |
| printk ("VFS: Unsupported blocksize on dev " |
| "%s.\n", bdevname(dev)); |
| goto failed_mount; |
| } |
| |
| if (sb->s_blocksize != sb->u.ext2_sb.s_frag_size) { |
| printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n", |
| sb->u.ext2_sb.s_frag_size, sb->s_blocksize); |
| goto failed_mount; |
| } |
| |
| if (sb->u.ext2_sb.s_blocks_per_group > sb->s_blocksize * 8) { |
| printk ("EXT2-fs: #blocks per group too big: %lu\n", |
| sb->u.ext2_sb.s_blocks_per_group); |
| goto failed_mount; |
| } |
| if (sb->u.ext2_sb.s_frags_per_group > sb->s_blocksize * 8) { |
| printk ("EXT2-fs: #fragments per group too big: %lu\n", |
| sb->u.ext2_sb.s_frags_per_group); |
| goto failed_mount; |
| } |
| if (sb->u.ext2_sb.s_inodes_per_group > sb->s_blocksize * 8) { |
| printk ("EXT2-fs: #inodes per group too big: %lu\n", |
| sb->u.ext2_sb.s_inodes_per_group); |
| goto failed_mount; |
| } |
| |
| sb->u.ext2_sb.s_groups_count = (le32_to_cpu(es->s_blocks_count) - |
| le32_to_cpu(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) { |
| printk ("EXT2-fs: not enough memory\n"); |
| goto failed_mount; |
| } |
| 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]) { |
| for (j = 0; j < i; j++) |
| brelse (sb->u.ext2_sb.s_group_desc[j]); |
| kfree(sb->u.ext2_sb.s_group_desc); |
| printk ("EXT2-fs: unable to read group descriptors\n"); |
| goto failed_mount; |
| } |
| } |
| if (!ext2_check_descriptors (sb)) { |
| printk ("EXT2-fs: group descriptors corrupted!\n"); |
| db_count = i; |
| goto failed_mount2; |
| } |
| 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_gdb_count = db_count; |
| /* |
| * set up enough so that it can read an inode |
| */ |
| sb->s_op = &ext2_sops; |
| sb->s_root = d_alloc_root(iget(sb, EXT2_ROOT_INO)); |
| if (!sb->s_root || !S_ISDIR(sb->s_root->d_inode->i_mode) || |
| !sb->s_root->d_inode->i_blocks || !sb->s_root->d_inode->i_size) { |
| if (sb->s_root) { |
| dput(sb->s_root); |
| sb->s_root = NULL; |
| printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n"); |
| } else |
| printk(KERN_ERR "EXT2-fs: get root inode failed\n"); |
| goto failed_mount2; |
| } |
| ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY); |
| return sb; |
| failed_mount2: |
| for (i = 0; i < db_count; i++) |
| brelse(sb->u.ext2_sb.s_group_desc[i]); |
| kfree(sb->u.ext2_sb.s_group_desc); |
| failed_mount: |
| brelse(bh); |
| return NULL; |
| } |
| |
| static void ext2_commit_super (struct super_block * sb, |
| struct ext2_super_block * es) |
| { |
| es->s_wtime = cpu_to_le32(CURRENT_TIME); |
| mark_buffer_dirty(sb->u.ext2_sb.s_sbh); |
| 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 (le16_to_cpu(es->s_state) & EXT2_VALID_FS) { |
| es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) & ~EXT2_VALID_FS); |
| es->s_mtime = cpu_to_le32(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. |
| */ |
| new_mount_opt = sb->u.ext2_sb.s_mount_opt; |
| 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 (le16_to_cpu(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 = cpu_to_le16(sb->u.ext2_sb.s_mount_state); |
| es->s_mtime = cpu_to_le32(CURRENT_TIME); |
| mark_buffer_dirty(sb->u.ext2_sb.s_sbh); |
| sb->s_dirt = 1; |
| ext2_commit_super (sb, es); |
| } |
| else { |
| int ret; |
| if ((ret = EXT2_HAS_RO_COMPAT_FEATURE(sb, |
| ~EXT2_FEATURE_RO_COMPAT_SUPP))) { |
| printk("EXT2-fs: %s: couldn't remount RDWR because of " |
| "unsupported optional features (%x).\n", |
| bdevname(sb->s_dev), ret); |
| return -EROFS; |
| } |
| /* |
| * 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 = le16_to_cpu(es->s_state); |
| if (!ext2_setup_super (sb, es, 0)) |
| sb->s_flags &= ~MS_RDONLY; |
| } |
| return 0; |
| } |
| |
| int ext2_statfs (struct super_block * sb, struct statfs * buf) |
| { |
| unsigned long overhead; |
| int i; |
| |
| if (test_opt (sb, MINIX_DF)) |
| overhead = 0; |
| else { |
| /* |
| * Compute the overhead (FS structures) |
| */ |
| |
| /* |
| * All of the blocks before first_data_block are |
| * overhead |
| */ |
| overhead = le32_to_cpu(sb->u.ext2_sb.s_es->s_first_data_block); |
| |
| /* |
| * Add the overhead attributed to the superblock and |
| * block group descriptors. If the sparse superblocks |
| * feature is turned on, then not all groups have this. |
| */ |
| for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) |
| overhead += ext2_bg_has_super(sb, i) + |
| ext2_bg_num_gdb(sb, i); |
| |
| /* |
| * Every block group has an inode bitmap, a block |
| * bitmap, and an inode table. |
| */ |
| overhead += (sb->u.ext2_sb.s_groups_count * |
| (2 + sb->u.ext2_sb.s_itb_per_group)); |
| } |
| |
| buf->f_type = EXT2_SUPER_MAGIC; |
| buf->f_bsize = sb->s_blocksize; |
| buf->f_blocks = le32_to_cpu(sb->u.ext2_sb.s_es->s_blocks_count) - overhead; |
| buf->f_bfree = ext2_count_free_blocks (sb); |
| buf->f_bavail = buf->f_bfree - le32_to_cpu(sb->u.ext2_sb.s_es->s_r_blocks_count); |
| if (buf->f_bfree < le32_to_cpu(sb->u.ext2_sb.s_es->s_r_blocks_count)) |
| buf->f_bavail = 0; |
| buf->f_files = le32_to_cpu(sb->u.ext2_sb.s_es->s_inodes_count); |
| buf->f_ffree = ext2_count_free_inodes (sb); |
| buf->f_namelen = EXT2_NAME_LEN; |
| return 0; |
| } |
| |
| static DECLARE_FSTYPE_DEV(ext2_fs_type, "ext2", ext2_read_super); |
| |
| static int __init init_ext2_fs(void) |
| { |
| return register_filesystem(&ext2_fs_type); |
| } |
| |
| static void __exit exit_ext2_fs(void) |
| { |
| unregister_filesystem(&ext2_fs_type); |
| } |
| |
| EXPORT_NO_SYMBOLS; |
| |
| module_init(init_ext2_fs) |
| module_exit(exit_ext2_fs) |