#include <linux/config.h>
#include <linux/module.h>
#include <linux/string.h>
+#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/buffer_head.h>
#include <linux/smp_lock.h>
#include <linux/vfs.h>
+#include <linux/seq_file.h>
+#include <linux/mount.h>
#include <asm/uaccess.h>
#include "ext2.h"
#include "xattr.h"
#include "acl.h"
+#include "xip.h"
static void ext2_sync_super(struct super_block *sb,
struct ext2_super_block *es);
static int ext2_remount (struct super_block * sb, int * flags, char * data);
static int ext2_statfs (struct super_block * sb, struct kstatfs * buf);
-static char error_buf[1024];
-
void ext2_error (struct super_block * sb, const char * function,
const char * fmt, ...)
{
cpu_to_le16(le16_to_cpu(es->s_state) | EXT2_ERROR_FS);
ext2_sync_super(sb, es);
}
- va_start (args, fmt);
- vsprintf (error_buf, fmt, args);
- va_end (args);
- if (test_opt (sb, ERRORS_PANIC))
- panic ("EXT2-fs panic (device %s): %s: %s\n",
- sb->s_id, function, error_buf);
- printk (KERN_CRIT "EXT2-fs error (device %s): %s: %s\n",
- sb->s_id, function, error_buf);
- if (test_opt (sb, ERRORS_RO)) {
- 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;
- struct ext2_sb_info *sbi = EXT2_SB(sb);
+ va_start(args, fmt);
+ printk(KERN_CRIT "EXT2-fs error (device %s): %s: ",sb->s_id, function);
+ vprintk(fmt, args);
+ printk("\n");
+ va_end(args);
- if (!(sb->s_flags & MS_RDONLY)) {
- sbi->s_mount_state |= EXT2_ERROR_FS;
- sbi->s_es->s_state =
- cpu_to_le16(le16_to_cpu(sbi->s_es->s_state) | EXT2_ERROR_FS);
- mark_buffer_dirty(sbi->s_sbh);
- sb->s_dirt = 1;
+ if (test_opt(sb, ERRORS_PANIC))
+ panic("EXT2-fs panic from previous error\n");
+ if (test_opt(sb, ERRORS_RO)) {
+ printk("Remounting filesystem read-only\n");
+ sb->s_flags |= MS_RDONLY;
}
- 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",
- sb->s_id, function, error_buf);
}
void ext2_warning (struct super_block * sb, const char * function,
{
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",
- sb->s_id, function, error_buf);
+ va_start(args, fmt);
+ printk(KERN_WARNING "EXT2-fs warning (device %s): %s: ",
+ sb->s_id, function);
+ vprintk(fmt, args);
+ printk("\n");
+ va_end(args);
}
void ext2_update_dynamic_rev(struct super_block *sb)
if (!(sb->s_flags & MS_RDONLY)) {
struct ext2_super_block *es = sbi->s_es;
- es->s_state = le16_to_cpu(sbi->s_mount_state);
+ es->s_state = cpu_to_le16(sbi->s_mount_state);
ext2_sync_super(sb, es);
}
db_count = sbi->s_gdb_count;
brelse (sbi->s_group_desc[i]);
kfree(sbi->s_group_desc);
kfree(sbi->s_debts);
+ percpu_counter_destroy(&sbi->s_freeblocks_counter);
+ percpu_counter_destroy(&sbi->s_freeinodes_counter);
+ percpu_counter_destroy(&sbi->s_dirs_counter);
brelse (sbi->s_sbh);
sb->s_fs_info = NULL;
kfree(sbi);
{
ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
sizeof(struct ext2_inode_info),
- 0, SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT,
+ 0, SLAB_RECLAIM_ACCOUNT,
init_once, NULL);
if (ext2_inode_cachep == NULL)
return -ENOMEM;
printk(KERN_INFO "ext2_inode_cache: not all structures were freed\n");
}
-#ifdef CONFIG_EXT2_FS_POSIX_ACL
-
static void ext2_clear_inode(struct inode *inode)
{
+#ifdef CONFIG_EXT2_FS_POSIX_ACL
struct ext2_inode_info *ei = EXT2_I(inode);
if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) {
posix_acl_release(ei->i_default_acl);
ei->i_default_acl = EXT2_ACL_NOT_CACHED;
}
+#endif
}
-#else
-# define ext2_clear_inode NULL
+static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
+{
+ struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb);
+
+ if (sbi->s_mount_opt & EXT2_MOUNT_GRPID)
+ seq_puts(seq, ",grpid");
+ else
+ seq_puts(seq, ",nogrpid");
+
+#if defined(CONFIG_QUOTA)
+ if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
+ seq_puts(seq, ",usrquota");
+
+ if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
+ seq_puts(seq, ",grpquota");
+#endif
+
+#if defined(CONFIG_EXT2_FS_XIP)
+ if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
+ seq_puts(seq, ",xip");
+#endif
+
+ return 0;
+}
+
+#ifdef CONFIG_QUOTA
+static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
+static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
#endif
static struct super_operations ext2_sops = {
.statfs = ext2_statfs,
.remount_fs = ext2_remount,
.clear_inode = ext2_clear_inode,
+ .show_options = ext2_show_options,
+#ifdef CONFIG_QUOTA
+ .quota_read = ext2_quota_read,
+ .quota_write = ext2_quota_write,
+#endif
};
+static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp)
+{
+ __u32 *objp = vobjp;
+ unsigned long ino = objp[0];
+ __u32 generation = objp[1];
+ struct inode *inode;
+ struct dentry *result;
+
+ if (ino != EXT2_ROOT_INO && ino < EXT2_FIRST_INO(sb))
+ return ERR_PTR(-ESTALE);
+ if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
+ return ERR_PTR(-ESTALE);
+
+ /* iget isn't really right if the inode is currently unallocated!!
+ * ext2_read_inode currently does appropriate checks, but
+ * it might be "neater" to call ext2_get_inode first and check
+ * if the inode is valid.....
+ */
+ inode = iget(sb, ino);
+ if (inode == NULL)
+ return ERR_PTR(-ENOMEM);
+ if (is_bad_inode(inode)
+ || (generation && inode->i_generation != generation)
+ ) {
+ /* we didn't find the right inode.. */
+ iput(inode);
+ return ERR_PTR(-ESTALE);
+ }
+ /* now to find a dentry.
+ * If possible, get a well-connected one
+ */
+ result = d_alloc_anon(inode);
+ if (!result) {
+ iput(inode);
+ return ERR_PTR(-ENOMEM);
+ }
+ return result;
+}
+
+
/* Yes, most of these are left as NULL!!
* A NULL value implies the default, which works with ext2-like file
* systems, but can be improved upon.
struct dentry *ext2_get_parent(struct dentry *child);
static struct export_operations ext2_export_ops = {
.get_parent = ext2_get_parent,
+ .get_dentry = ext2_get_dentry,
};
static unsigned long get_sb_block(void **data)
enum {
Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
- Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
- Opt_nouid32, Opt_check, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov, Opt_nobh,
- Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
- Opt_ignore, Opt_err,
+ Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
+ Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
+ Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
+ Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
+ Opt_usrquota, Opt_grpquota, Opt_tagxid
};
static match_table_t tokens = {
{Opt_nouid32, "nouid32"},
{Opt_nocheck, "check=none"},
{Opt_nocheck, "nocheck"},
- {Opt_check, "check"},
{Opt_debug, "debug"},
{Opt_oldalloc, "oldalloc"},
{Opt_orlov, "orlov"},
{Opt_nouser_xattr, "nouser_xattr"},
{Opt_acl, "acl"},
{Opt_noacl, "noacl"},
- {Opt_ignore, "grpquota"},
+ {Opt_xip, "xip"},
+ {Opt_tagxid, "tagxid"},
+ {Opt_grpquota, "grpquota"},
{Opt_ignore, "noquota"},
- {Opt_ignore, "quota"},
- {Opt_ignore, "usrquota"},
+ {Opt_quota, "quota"},
+ {Opt_usrquota, "usrquota"},
{Opt_err, NULL}
};
case Opt_nouid32:
set_opt (sbi->s_mount_opt, NO_UID32);
break;
- case Opt_check:
-#ifdef CONFIG_EXT2_CHECK
- set_opt (sbi->s_mount_opt, CHECK);
-#else
- printk("EXT2 Check option not supported\n");
-#endif
+#ifndef CONFIG_INOXID_NONE
+ case Opt_tagxid:
+ set_opt (sbi->s_mount_opt, TAGXID);
break;
+#endif
case Opt_nocheck:
clear_opt (sbi->s_mount_opt, CHECK);
break;
printk("EXT2 (no)acl options not supported\n");
break;
#endif
+ case Opt_xip:
+#ifdef CONFIG_EXT2_FS_XIP
+ set_opt (sbi->s_mount_opt, XIP);
+#else
+ printk("EXT2 xip option not supported\n");
+#endif
+ break;
+
+#if defined(CONFIG_QUOTA)
+ case Opt_quota:
+ case Opt_usrquota:
+ set_opt(sbi->s_mount_opt, USRQUOTA);
+ break;
+
+ case Opt_grpquota:
+ set_opt(sbi->s_mount_opt, GRPQUOTA);
+ break;
+#else
+ case Opt_quota:
+ case Opt_usrquota:
+ case Opt_grpquota:
+ printk(KERN_ERR
+ "EXT2-fs: quota operations not supported.\n");
+
+ break;
+#endif
+
case Opt_ignore:
break;
default:
(le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
printk ("EXT2-fs warning: checktime reached, "
"running e2fsck is recommended\n");
- if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
- es->s_max_mnt_count = (__s16) cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
+ if (!le16_to_cpu(es->s_max_mnt_count))
+ es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
ext2_write_super(sb);
if (test_opt (sb, DEBUG))
EXT2_BLOCKS_PER_GROUP(sb),
EXT2_INODES_PER_GROUP(sb),
sbi->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 loff_t ext2_max_size(int bits)
{
loff_t res = EXT2_NDIR_BLOCKS;
+ /* This constant is calculated to be the largest file size for a
+ * dense, 4k-blocksize file such that the total number of
+ * sectors in the file, including data and all indirect blocks,
+ * does not exceed 2^32. */
+ const loff_t upper_limit = 0x1ff7fffd000LL;
+
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);
+ if (res > upper_limit)
+ res = upper_limit;
return res;
}
int blocksize = BLOCK_SIZE;
int db_count;
int i, j;
+ __le32 features;
sbi = kmalloc(sizeof(*sbi), GFP_KERNEL);
if (!sbi)
es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
sbi->s_es = es;
sb->s_magic = le16_to_cpu(es->s_magic);
- sb->s_flags |= MS_ONE_SECOND;
- if (sb->s_magic != EXT2_SUPER_MAGIC) {
- if (!silent)
- printk ("VFS: Can't find ext2 filesystem on dev %s.\n",
- sb->s_id);
- goto failed_mount;
- }
+
+ if (sb->s_magic != EXT2_SUPER_MAGIC)
+ goto cantfind_ext2;
/* Set defaults before we parse the mount options */
def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
if (!parse_options ((char *) data, sbi))
goto failed_mount;
+ if (EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_TAGXID)
+ sb->s_flags |= MS_TAGXID;
sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
MS_POSIXACL : 0);
+ ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
+ EXT2_MOUNT_XIP if not */
+
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) ||
* 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))) {
+ features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
+ if (features) {
printk("EXT2-fs: %s: couldn't mount because of "
"unsupported optional features (%x).\n",
- sb->s_id, i);
+ sb->s_id, le32_to_cpu(features));
goto failed_mount;
}
if (!(sb->s_flags & MS_RDONLY) &&
- (i = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
+ (features = 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",
- sb->s_id, i);
+ sb->s_id, le32_to_cpu(features));
goto failed_mount;
}
+
blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
+
+ if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) ||
+ (sb->s_blocksize != blocksize))) {
+ if (!silent)
+ printk("XIP: Unsupported blocksize\n");
+ goto failed_mount;
+ }
+
/* If the blocksize doesn't match, re-read the thing.. */
if (sb->s_blocksize != blocksize) {
brelse(bh);
}
es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
sbi->s_es = es;
- if (es->s_magic != le16_to_cpu(EXT2_SUPER_MAGIC)) {
+ if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
printk ("EXT2-fs: Magic mismatch, very weird !\n");
goto failed_mount;
}
goto failed_mount;
}
}
+
sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
le32_to_cpu(es->s_log_frag_size);
- if (sbi->s_frag_size)
- sbi->s_frags_per_block = sb->s_blocksize /
- sbi->s_frag_size;
- else
- sb->s_magic = 0;
+ if (sbi->s_frag_size == 0)
+ goto cantfind_ext2;
+ sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
+
sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
- sbi->s_inodes_per_block = sb->s_blocksize /
- EXT2_INODE_SIZE(sb);
+
+ if (EXT2_INODE_SIZE(sb) == 0)
+ goto cantfind_ext2;
+ sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
+ if (sbi->s_inodes_per_block == 0)
+ goto cantfind_ext2;
sbi->s_itb_per_group = sbi->s_inodes_per_group /
- sbi->s_inodes_per_block;
+ sbi->s_inodes_per_block;
sbi->s_desc_per_block = sb->s_blocksize /
- sizeof (struct ext2_group_desc);
+ sizeof (struct ext2_group_desc);
sbi->s_sbh = bh;
sbi->s_mount_state = le16_to_cpu(es->s_state);
sbi->s_addr_per_block_bits =
log2 (EXT2_ADDR_PER_BLOCK(sb));
sbi->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",
- sb->s_id);
- goto failed_mount;
- }
+
+ if (sb->s_magic != EXT2_SUPER_MAGIC)
+ goto cantfind_ext2;
+
if (sb->s_blocksize != bh->b_size) {
if (!silent)
printk ("VFS: Unsupported blocksize on dev "
goto failed_mount;
}
+ if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
+ goto cantfind_ext2;
sbi->s_groups_count = (le32_to_cpu(es->s_blocks_count) -
le32_to_cpu(es->s_first_data_block) +
EXT2_BLOCKS_PER_GROUP(sb) - 1) /
*/
sb->s_op = &ext2_sops;
sb->s_export_op = &ext2_export_ops;
+ sb->s_xattr = ext2_xattr_handlers;
root = iget(sb, EXT2_ROOT_INO);
sb->s_root = d_alloc_root(root);
if (!sb->s_root) {
}
if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
ext2_warning(sb, __FUNCTION__,
- "mounting ext3 filesystem as ext2\n");
+ "mounting ext3 filesystem as ext2");
ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
percpu_counter_mod(&sbi->s_freeblocks_counter,
ext2_count_free_blocks(sb));
percpu_counter_mod(&sbi->s_dirs_counter,
ext2_count_dirs(sb));
return 0;
+
+cantfind_ext2:
+ if (!silent)
+ printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
+ sb->s_id);
+ goto failed_mount;
+
failed_mount2:
for (i = 0; i < db_count; i++)
brelse(sbi->s_group_desc[i]);
failed_mount_group_desc:
kfree(sbi->s_group_desc);
- if (sbi->s_debts)
- kfree(sbi->s_debts);
+ kfree(sbi->s_debts);
failed_mount:
brelse(bh);
failed_sbi:
{
struct ext2_sb_info * sbi = EXT2_SB(sb);
struct ext2_super_block * es;
+ unsigned long old_mount_opt = sbi->s_mount_opt;
+ struct ext2_mount_options old_opts;
+ unsigned long old_sb_flags;
+ int err;
+
+ /* Store the old options */
+ old_sb_flags = sb->s_flags;
+ old_opts.s_mount_opt = sbi->s_mount_opt;
+ old_opts.s_resuid = sbi->s_resuid;
+ old_opts.s_resgid = sbi->s_resgid;
/*
* Allow the "check" option to be passed as a remount option.
*/
- if (!parse_options (data, sbi))
+ if (!parse_options (data, sbi)) {
+ err = -EINVAL;
+ goto restore_opts;
+ }
+
+ if ((sbi->s_mount_opt & EXT2_MOUNT_TAGXID) &&
+ !(sb->s_flags & MS_TAGXID)) {
+ printk("EXT2-fs: %s: tagxid not permitted on remount.\n",
+ sb->s_id);
return -EINVAL;
+ }
sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
es = sbi->s_es;
+ if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
+ (old_mount_opt & EXT2_MOUNT_XIP)) &&
+ invalidate_inodes(sb))
+ ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
+ "xip remain in cache (no functional problem)");
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
return 0;
if (*flags & MS_RDONLY) {
es->s_state = cpu_to_le16(sbi->s_mount_state);
es->s_mtime = cpu_to_le32(get_seconds());
} else {
- int ret;
- if ((ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
- ~EXT2_FEATURE_RO_COMPAT_SUPP))) {
+ __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
+ ~EXT2_FEATURE_RO_COMPAT_SUPP);
+ if (ret) {
printk("EXT2-fs: %s: couldn't remount RDWR because of "
"unsupported optional features (%x).\n",
- sb->s_id, ret);
- return -EROFS;
+ sb->s_id, le32_to_cpu(ret));
+ err = -EROFS;
+ goto restore_opts;
}
/*
* Mounting a RDONLY partition read-write, so reread and
}
ext2_sync_super(sb, es);
return 0;
+restore_opts:
+ sbi->s_mount_opt = old_opts.s_mount_opt;
+ sbi->s_resuid = old_opts.s_resuid;
+ sbi->s_resgid = old_opts.s_resgid;
+ sb->s_flags = old_sb_flags;
+ return err;
}
static int ext2_statfs (struct super_block * sb, struct kstatfs * buf)
return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
}
+#ifdef CONFIG_QUOTA
+
+/* Read data from quotafile - avoid pagecache and such because we cannot afford
+ * acquiring the locks... As quota files are never truncated and quota code
+ * itself serializes the operations (and noone else should touch the files)
+ * we don't have to be afraid of races */
+static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
+ size_t len, loff_t off)
+{
+ struct inode *inode = sb_dqopt(sb)->files[type];
+ sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
+ int err = 0;
+ int offset = off & (sb->s_blocksize - 1);
+ int tocopy;
+ size_t toread;
+ struct buffer_head tmp_bh;
+ struct buffer_head *bh;
+ loff_t i_size = i_size_read(inode);
+
+ if (off > i_size)
+ return 0;
+ if (off+len > i_size)
+ len = i_size-off;
+ toread = len;
+ while (toread > 0) {
+ tocopy = sb->s_blocksize - offset < toread ?
+ sb->s_blocksize - offset : toread;
+
+ tmp_bh.b_state = 0;
+ err = ext2_get_block(inode, blk, &tmp_bh, 0);
+ if (err)
+ return err;
+ if (!buffer_mapped(&tmp_bh)) /* A hole? */
+ memset(data, 0, tocopy);
+ else {
+ bh = sb_bread(sb, tmp_bh.b_blocknr);
+ if (!bh)
+ return -EIO;
+ memcpy(data, bh->b_data+offset, tocopy);
+ brelse(bh);
+ }
+ offset = 0;
+ toread -= tocopy;
+ data += tocopy;
+ blk++;
+ }
+ return len;
+}
+
+/* Write to quotafile */
+static ssize_t ext2_quota_write(struct super_block *sb, int type,
+ const char *data, size_t len, loff_t off)
+{
+ struct inode *inode = sb_dqopt(sb)->files[type];
+ sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
+ int err = 0;
+ int offset = off & (sb->s_blocksize - 1);
+ int tocopy;
+ size_t towrite = len;
+ struct buffer_head tmp_bh;
+ struct buffer_head *bh;
+
+ mutex_lock(&inode->i_mutex);
+ while (towrite > 0) {
+ tocopy = sb->s_blocksize - offset < towrite ?
+ sb->s_blocksize - offset : towrite;
+
+ tmp_bh.b_state = 0;
+ err = ext2_get_block(inode, blk, &tmp_bh, 1);
+ if (err)
+ goto out;
+ if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
+ bh = sb_bread(sb, tmp_bh.b_blocknr);
+ else
+ bh = sb_getblk(sb, tmp_bh.b_blocknr);
+ if (!bh) {
+ err = -EIO;
+ goto out;
+ }
+ lock_buffer(bh);
+ memcpy(bh->b_data+offset, data, tocopy);
+ flush_dcache_page(bh->b_page);
+ set_buffer_uptodate(bh);
+ mark_buffer_dirty(bh);
+ unlock_buffer(bh);
+ brelse(bh);
+ offset = 0;
+ towrite -= tocopy;
+ data += tocopy;
+ blk++;
+ }
+out:
+ if (len == towrite)
+ return err;
+ if (inode->i_size < off+len-towrite)
+ i_size_write(inode, off+len-towrite);
+ inode->i_version++;
+ inode->i_mtime = inode->i_ctime = CURRENT_TIME;
+ mark_inode_dirty(inode);
+ mutex_unlock(&inode->i_mutex);
+ return len - towrite;
+}
+
+#endif
+
static struct file_system_type ext2_fs_type = {
.owner = THIS_MODULE,
.name = "ext2",