From: Jan Kara <jack@suse.cz>
Attached patch adds functions ufs_quota_read() and ufs_quota_write() to the
UFS code. So quotas for UFS should work again (they were broken by the
quota io redesign). I don't actually think the patch is too much important
as I'm not sure anybody uses quotas on UFS but we're in the "stable" branch
so just dropping a support did not seem right to me.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/fs/ufs/super.c | 99 +++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 99 insertions(+)
diff -puN fs/ufs/super.c~fix-ufs-quota fs/ufs/super.c
--- 25/fs/ufs/super.c~fix-ufs-quota 2005-03-07 20:41:39.000000000 -0800
+++ 25-akpm/fs/ufs/super.c 2005-03-07 20:41:39.000000000 -0800
@@ -1196,6 +1196,11 @@ static void destroy_inodecache(void)
printk(KERN_INFO "ufs_inode_cache: not all structures were freed\n");
}
+#ifdef CONFIG_QUOTA
+static ssize_t ufs_quota_read(struct super_block *, int, char *,size_t, loff_t);
+static ssize_t ufs_quota_write(struct super_block *, int, const char *, size_t, loff_t);
+#endif
+
static struct super_operations ufs_super_ops = {
.alloc_inode = ufs_alloc_inode,
.destroy_inode = ufs_destroy_inode,
@@ -1206,8 +1211,102 @@ static struct super_operations ufs_super
.write_super = ufs_write_super,
.statfs = ufs_statfs,
.remount_fs = ufs_remount,
+#ifdef CONFIG_QUOTA
+ .quota_read = ufs_quota_read,
+ .quota_write = ufs_quota_write,
+#endif
};
+#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 ufs_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 >> sb->s_blocksize_bits;
+ int err = 0;
+ int offset = off & (sb->s_blocksize - 1);
+ int tocopy;
+ size_t toread;
+ 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;
+
+ bh = ufs_bread(inode, blk, 0, &err);
+ if (err)
+ return err;
+ if (!bh) /* A hole? */
+ memset(data, 0, tocopy);
+ else {
+ memcpy(data, bh->b_data+offset, tocopy);
+ brelse(bh);
+ }
+ offset = 0;
+ toread -= tocopy;
+ data += tocopy;
+ blk++;
+ }
+ return len;
+}
+
+/* Write to quotafile */
+static ssize_t ufs_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 >> sb->s_blocksize_bits;
+ int err = 0;
+ int offset = off & (sb->s_blocksize - 1);
+ int tocopy;
+ size_t towrite = len;
+ struct buffer_head *bh;
+
+ down(&inode->i_sem);
+ while (towrite > 0) {
+ tocopy = sb->s_blocksize - offset < towrite ?
+ sb->s_blocksize - offset : towrite;
+
+ bh = ufs_bread(inode, blk, 1, &err);
+ if (!bh)
+ 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_SEC;
+ mark_inode_dirty(inode);
+ up(&inode->i_sem);
+ return len - towrite;
+}
+
+#endif
+
static struct super_block *ufs_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
_