Index: linux-2.6.7/fs/ext3/ialloc.c
===================================================================
--- linux-2.6.7.orig/fs/ext3/ialloc.c	2004-08-27 14:28:16.000000000 +0800
+++ linux-2.6.7/fs/ext3/ialloc.c	2004-08-27 14:29:21.000000000 +0800
@@ -43,6 +43,24 @@
  * the free blocks count in the block.
  */
 
+/*
+ * this is very simple policy: files with O_INRESERVE goes to last group;
+ * files with no O_INRESERVE goes to all groups, but last. probably we'll
+ * specify group for O_INRESERVE files later -bzzz */
+static inline int ext3_group_allowed(struct super_block *sb, int mode, int group)
+{
+	if (!test_opt(sb, INRESERVE) || EXT3_SB(sb)->s_groups_count == 1)
+		return 1;
+
+	if (mode & EXT3_S_INRESERVE) {
+		if (group != EXT3_SB(sb)->s_groups_count - 1)
+			return 0;
+	} else {
+		if (group == EXT3_SB(sb)->s_groups_count -1 )
+			return 0;
+	}
+	return 1;
+}
 
 /*
  * Read the inode allocation bitmap for a given block_group, reading
@@ -203,7 +221,7 @@
  * For other inodes, search forward from the parent directory\'s block
  * group to find a free inode.
  */
-static int find_group_dir(struct super_block *sb, struct inode *parent)
+static int find_group_dir(struct super_block *sb, struct inode *parent, int mode)
 {
 	int ngroups = EXT3_SB(sb)->s_groups_count;
 	int freei, avefreei;
@@ -215,6 +233,8 @@
 	avefreei = freei / ngroups;
 
 	for (group = 0; group < ngroups; group++) {
+	        if (!ext3_group_allowed(sb, mode, group))
+	        	continue;
 		desc = ext3_get_group_desc (sb, group, &bh);
 		if (!desc || !desc->bg_free_inodes_count)
 			continue;
@@ -258,7 +278,7 @@
 #define INODE_COST 64
 #define BLOCK_COST 256
 
-static int find_group_orlov(struct super_block *sb, struct inode *parent)
+static int find_group_orlov(struct super_block *sb, struct inode *parent, int mode)
 {
 	int parent_group = EXT3_I(parent)->i_block_group;
 	struct ext3_sb_info *sbi = EXT3_SB(sb);
@@ -288,6 +308,8 @@
 		parent_group = (unsigned)group % ngroups;
 		for (i = 0; i < ngroups; i++) {
 			group = (parent_group + i) % ngroups;
+			if (!ext3_group_allowed(sb, mode, group))
+				continue;
 			desc = ext3_get_group_desc (sb, group, &bh);
 			if (!desc || !desc->bg_free_inodes_count)
 				continue;
@@ -357,7 +379,7 @@
 	return -1;
 }
 
-static int find_group_other(struct super_block *sb, struct inode *parent)
+static int find_group_other(struct super_block *sb, struct inode *parent, int mode)
 {
 	int parent_group = EXT3_I(parent)->i_block_group;
 	int ngroups = EXT3_SB(sb)->s_groups_count;
@@ -393,6 +415,8 @@
 		group += i;
 		if (group >= ngroups)
 			group -= ngroups;
+		if (!ext3_group_allowed(sb, mode, group))
+			continue;
 		desc = ext3_get_group_desc (sb, group, &bh);
 		if (desc && le16_to_cpu(desc->bg_free_inodes_count) &&
 				le16_to_cpu(desc->bg_free_blocks_count))
@@ -407,6 +431,8 @@
 	for (i = 0; i < ngroups; i++) {
 		if (++group >= ngroups)
 			group = 0;
+		if (!ext3_group_allowed(sb, mode, group))
+			continue;
 		desc = ext3_get_group_desc (sb, group, &bh);
 		if (desc && le16_to_cpu(desc->bg_free_inodes_count))
 			return group;
@@ -502,40 +528,41 @@
 continue_allocation:
 	if (S_ISDIR(mode)) {
 		if (test_opt (sb, OLDALLOC))
-			group = find_group_dir(sb, dir);
+			group = find_group_dir(sb, dir, mode);
 		else
-			group = find_group_orlov(sb, dir);
+			group = find_group_orlov(sb, dir, mode);
 	} else 
-		group = find_group_other(sb, dir);
+		group = find_group_other(sb, dir, mode);
 
 	err = -ENOSPC;
 	if (group == -1)
 		goto out;
 
 	for (i = 0; i < sbi->s_groups_count; i++) {
-		gdp = ext3_get_group_desc(sb, group, &bh2);
+  		if (ext3_group_allowed(sb, mode, group)) {
+			gdp = ext3_get_group_desc(sb, group, &bh2);
 
-		err = -EIO;
-		brelse(bitmap_bh);
-		bitmap_bh = read_inode_bitmap(sb, group);
-		if (!bitmap_bh)
-			goto fail;
+			err = -EIO;
+			brelse(bitmap_bh);
+			bitmap_bh = read_inode_bitmap(sb, group);
+			if (!bitmap_bh)
+				goto fail;
+
+			ino = 0;
+
+	repeat_in_this_group:
+			ino = ext3_find_next_zero_bit((unsigned long *)
+					bitmap_bh->b_data, EXT3_INODES_PER_GROUP(sb), ino);
+			if (ino < EXT3_INODES_PER_GROUP(sb)) {
+				if (ext3_test_allocatable(ino, bitmap_bh)) { 
+					goto got;
+				}
+				J_ASSERT_BH(bitmap_bh, bh2jh(bitmap_bh)->b_committed_data);
 
-		ino = 0;
-
-repeat_in_this_group:
-		ino = ext3_find_next_zero_bit((unsigned long *)
-				bitmap_bh->b_data, EXT3_INODES_PER_GROUP(sb), ino);
-		if (ino < EXT3_INODES_PER_GROUP(sb)) {
-			if (ext3_test_allocatable(ino, bitmap_bh)) { 
-				goto got;
+				if (++ino < EXT3_INODES_PER_GROUP(sb))
+					goto repeat_in_this_group;
 			}
-			J_ASSERT_BH(bitmap_bh, bh2jh(bitmap_bh)->b_committed_data);
-
-			if (++ino < EXT3_INODES_PER_GROUP(sb))
-				goto repeat_in_this_group;
 		}
-
 		/*
 		 * This case is possible in concurrent environment.  It is very
 		 * rare.  We cannot repeat the find_group_xxx() call because
@@ -548,7 +575,6 @@
 	}
 	err = -ENOSPC;
 	goto out;
-
 got:
         BUFFER_TRACE(bitmap_bh, "get_undo_access");
         err = ext3_journal_get_undo_access(handle, bitmap_bh, NULL);
@@ -567,6 +593,7 @@
         if (buffer_jbd(bitmap_bh) && bh2jh(bitmap_bh)->b_committed_data)
 		J_ASSERT_BH(bitmap_bh, !ext3_test_bit(ino, bh2jh(bitmap_bh)->b_committed_data));
 	
+ 	J_ASSERT(ext3_group_allowed(sb, mode, group));	
 	ino += group * EXT3_INODES_PER_GROUP(sb) + 1;
 	if (ino < EXT3_FIRST_INO(sb) || ino > le32_to_cpu(es->s_inodes_count)) {
 		ext3_error (sb, "ext3_new_inode",
@@ -605,7 +632,7 @@
 			mode |= S_ISGID;
 	} else
 		inode->i_gid = current->fsgid;
-	inode->i_mode = mode;
+	inode->i_mode = mode & ~EXT3_S_INRESERVE;
 
 	inode->i_ino = ino;
 	/* This is the optimal IO size (for stat), not the fs block size */
Index: linux-2.6.7/fs/ext3/super.c
===================================================================
--- linux-2.6.7.orig/fs/ext3/super.c	2004-08-27 12:04:38.000000000 +0800
+++ linux-2.6.7/fs/ext3/super.c	2004-08-27 14:28:22.000000000 +0800
@@ -644,6 +644,7 @@
 	{Opt_iopen_nopriv,  "iopen_nopriv"},
  	{Opt_extents, "extents"},
  	{Opt_extdebug, "extdebug"},
+	{Opt_inrsv,    "inrsv"},
 	{Opt_err, NULL}
 };
 
@@ -929,6 +930,10 @@
 		case Opt_extdebug:
 			set_opt (sbi->s_mount_opt, EXTDEBUG);
 			break;
+		case Opt_inrsv:
+			set_opt (sbi->s_mount_opt, INRESERVE);
+ 			J_ASSERT((EXT3_S_INRESERVE & S_IALLUGO) == 0);
+		        break;	
 		default:
 			printk (KERN_ERR
 				"EXT3-fs: Unrecognized mount option \"%s\" "
Index: linux-2.6.7/fs/ext3/namei.c
===================================================================
--- linux-2.6.7.orig/fs/ext3/namei.c	2004-08-27 13:03:21.000000000 +0800
+++ linux-2.6.7/fs/ext3/namei.c	2004-08-27 14:36:09.000000000 +0800
@@ -1701,6 +1701,36 @@
 	return err;
 }
 
+static int ext3_create_it (struct inode * dir, struct dentry * dentry, int mode,
+				struct lookup_intent *it)
+{
+	handle_t *handle; 
+	struct inode * inode;
+	int err;
+
+	handle = ext3_journal_start(dir, EXT3_DATA_TRANS_BLOCKS +
+					EXT3_INDEX_EXTRA_TRANS_BLOCKS + 3);
+	if (IS_ERR(handle)) {
+		return PTR_ERR(handle);
+	}
+
+	if (IS_SYNC(dir))
+		handle->h_sync = 1;
+
+	if (it && it->it_flags & O_INRESERVE)
+		mode |= EXT3_S_INRESERVE;
+	inode = ext3_new_inode_wantedi (handle, dir, mode, dentry);
+	err = PTR_ERR(inode);
+	if (!IS_ERR(inode)) {
+		inode->i_op = &ext3_file_inode_operations;
+		inode->i_fop = &ext3_file_operations;
+		ext3_set_aops(inode);
+		err = ext3_add_nondir(handle, dentry, inode);
+	}
+	ext3_journal_stop(handle, dir);
+	return err;
+}
+
 static int ext3_mknod (struct inode * dir, struct dentry *dentry,
 			int mode, dev_t rdev)
 {
@@ -2462,6 +2492,7 @@
  */
 struct inode_operations ext3_dir_inode_operations = {
 	.create		= ext3_create,
+ 	.create_it	= ext3_create_it,		/* BKL held */
 	.lookup		= ext3_lookup,
 	.link		= ext3_link,
 	.unlink		= ext3_unlink,
Index: linux-2.6.7/include/asm-i386/fcntl.h
===================================================================
--- linux-2.6.7.orig/include/asm-i386/fcntl.h	2004-06-16 13:19:35.000000000 +0800
+++ linux-2.6.7/include/asm-i386/fcntl.h	2004-08-27 14:28:22.000000000 +0800
@@ -20,6 +20,7 @@
 #define O_LARGEFILE	0100000
 #define O_DIRECTORY	0200000	/* must be a directory */
 #define O_NOFOLLOW	0400000 /* don't follow links */
+#define O_INRESERVE	01000000 /* allocate inodes in reserved space */
 
 #define F_DUPFD		0	/* dup */
 #define F_GETFD		1	/* get close_on_exec */
Index: linux-2.6.7/include/linux/ext3_fs.h
===================================================================
--- linux-2.6.7.orig/include/linux/ext3_fs.h	2004-08-27 13:03:21.000000000 +0800
+++ linux-2.6.7/include/linux/ext3_fs.h	2004-08-27 14:28:22.000000000 +0800
@@ -343,6 +343,7 @@
 #define EXT3_MOUNT_EXTDEBUG		0x20000	/* Extents debug */
 #define EXT3_MOUNT_IOPEN		0x40000	/* Allow access via iopen */
 #define EXT3_MOUNT_IOPEN_NOPRIV		0x80000	/* Make iopen world-readable */
+#define EXT3_MOUNT_INRESERVE		0x400000/* reserve one group for O_INRESERVE */
 
 /* Compatibility, for having both ext2_fs.h and ext3_fs.h included at once */
 #ifndef clear_opt
@@ -493,6 +494,8 @@
 
 #define EXT3_GOOD_OLD_INODE_SIZE 128
 
+#define EXT3_S_INRESERVE	01000000
+
 /*
  * Feature set definitions
  */