Index: linux-2.4.24/fs/ext3/ialloc.c
===================================================================
--- linux-2.4.24.orig/fs/ext3/ialloc.c	2004-08-02 22:13:13.000000000 +0400
+++ linux-2.4.24/fs/ext3/ialloc.c	2004-08-04 01:10:30.000000000 +0400
@@ -41,6 +41,24 @@
  * when a file system is mounted (see ext3_read_super).
  */
 
+/*
+ * 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
@@ -337,20 +355,33 @@
 	return !ext3_test_bit(nr, bh2jh(bh)->b_committed_data);
 }
 
-int ext3_find_group_dir(const struct inode *dir,
+int ext3_find_group_dir(const struct inode *dir, int mode,
 				struct ext3_group_desc **gdp,
 				struct buffer_head **bh)
 {
 	struct super_block *sb = dir->i_sb;
 	struct ext3_super_block *es;
 	struct ext3_group_desc *tmp;
-	int i = 0, j, avefreei;
+	int i = 0, j, ifree, avefreei;
 
 	es = EXT3_SB(sb)->s_es;
-	avefreei = le32_to_cpu(es->s_free_inodes_count) /
-			sb->u.ext3_sb.s_groups_count;
+	ifree = le32_to_cpu(es->s_free_inodes_count);
+	j = sb->u.ext3_sb.s_groups_count; 
+	if (test_opt(sb, INRESERVE) && EXT3_SB(sb)->s_groups_count > 1) {
+		tmp = ext3_get_group_desc(sb, EXT3_SB(sb)->s_groups_count-1, NULL);
+		if (mode & EXT3_S_INRESERVE) {
+			ifree = le16_to_cpu(tmp->bg_free_blocks_count);
+			j = 1;
+		} else {
+			ifree -= le16_to_cpu(tmp->bg_free_blocks_count);
+			j--;
+		}
+	}
+	avefreei = ifree / j;
 	for (j = 0; j < sb->u.ext3_sb.s_groups_count; j++) {
 		struct buffer_head *temp_buffer;
+		if (!ext3_group_allowed(sb, mode, j))
+			continue;
 		tmp = ext3_get_group_desc(sb, j, &temp_buffer);
 		if (tmp && le16_to_cpu(tmp->bg_free_inodes_count) &&
 			le16_to_cpu(tmp->bg_free_inodes_count) >= avefreei) {
@@ -366,7 +397,7 @@
 	return i;
 }
 
-int ext3_find_group_other(const struct inode *dir,
+int ext3_find_group_other(const struct inode *dir, int mode,
 				struct ext3_group_desc **gdp,
 				struct buffer_head **bh)
 {
@@ -379,7 +410,8 @@
 	 */
 	i = dir->u.ext3_i.i_block_group;
 	tmp = ext3_get_group_desc(sb, i, bh);
-	if (tmp && le16_to_cpu(tmp->bg_free_inodes_count))
+	if (tmp && le16_to_cpu(tmp->bg_free_inodes_count)
+			&& ext3_group_allowed(sb, mode, i))
 		*gdp = tmp;
 	else {
 		/*
@@ -390,6 +422,8 @@
 			i += j;
 			if (i >= sb->u.ext3_sb.s_groups_count)
 				i -= sb->u.ext3_sb.s_groups_count;
+			if (!ext3_group_allowed(sb, mode, i))
+				continue;
 			tmp = ext3_get_group_desc (sb, i, bh);
 			if (tmp && le16_to_cpu(tmp->bg_free_inodes_count)) {
 				*gdp = tmp;
@@ -405,6 +439,8 @@
 		for (j = 2; j < sb->u.ext3_sb.s_groups_count; j++) {
 			if (++i >= sb->u.ext3_sb.s_groups_count)
 				i = 0;
+			if (!ext3_group_allowed(sb, mode, i))
+				continue;
 			tmp = ext3_get_group_desc (sb, i, bh);
 			if (tmp && le16_to_cpu(tmp->bg_free_inodes_count)) {
 				*gdp = tmp;
@@ -421,8 +457,8 @@
 				struct buffer_head **bh)
 {
 	if (S_ISDIR(mode))
-		return ext3_find_group_dir(dir, gdp, bh);
-	return ext3_find_group_other(dir, gdp, bh);
+		return ext3_find_group_dir(dir, mode, gdp, bh);
+	return ext3_find_group_other(dir, mode, gdp, bh);
 }
 
 static int ext3_find_usable_inode(struct super_block *sb,
@@ -549,6 +585,8 @@
 	for (i = i + 1; i != k; i++) {
 		if (i >= sb->u.ext3_sb.s_groups_count)
 			i = 0;
+		if (!ext3_group_allowed(sb, mode, i))
+			continue;
 		tmp = ext3_get_group_desc(sb, i, &bh2);
 		if (le16_to_cpu(tmp->bg_free_inodes_count) == 0)
 			continue;
@@ -588,6 +626,7 @@
 	if (buffer_jbd(bh) && bh2jh(bh)->b_committed_data)
 		J_ASSERT_BH(bh, !ext3_test_bit(j, bh2jh(bh)->b_committed_data));
 
+	J_ASSERT(ext3_group_allowed(sb, mode, i));
 	j += i * EXT3_INODES_PER_GROUP(sb) + 1;
 	if (j < EXT3_FIRST_INO(sb) || j > le32_to_cpu(es->s_inodes_count)) {
 		ext3_error (sb, "ext3_new_inode",
@@ -628,7 +667,7 @@
 			mode |= S_ISGID;
 	} else
 		inode->i_gid = current->fsgid;
-	inode->i_mode = mode;
+	inode->i_mode = mode & ~EXT3_S_INRESERVE;
 
 	inode->i_ino = j;
 	/* This is the optimal IO size (for stat), not the fs block size */
Index: linux-2.4.24/fs/ext3/super.c
===================================================================
--- linux-2.4.24.orig/fs/ext3/super.c	2004-08-02 22:13:12.000000000 +0400
+++ linux-2.4.24/fs/ext3/super.c	2004-08-04 00:10:07.000000000 +0400
@@ -723,6 +723,10 @@
 				return 0;
 			*resgid = v;
 		}
+		else if (!strcmp (this_char, "inrsv")) {
+			set_opt (*mount_options, INRESERVE);
+			J_ASSERT((EXT3_S_INRESERVE & S_IALLUGO) == 0);
+		}
 		else if (!strcmp (this_char, "resuid")) {
 			unsigned long v;
 			if (want_numeric(value, "resuid", &v))
Index: linux-2.4.24/fs/ext3/namei.c
===================================================================
--- linux-2.4.24.orig/fs/ext3/namei.c	2004-08-02 22:13:13.000000000 +0400
+++ linux-2.4.24/fs/ext3/namei.c	2004-08-03 03:21:09.000000000 +0400
@@ -1971,6 +1971,36 @@
 	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;
+		inode->i_mapping->a_ops = &ext3_aops;
+		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, int rdev)
 {
@@ -2803,6 +2833,7 @@
  */
 struct inode_operations ext3_dir_inode_operations = {
 	create:		ext3_create,		/* BKL held */
+	create_it:	ext3_create_it,		/* BKL held */
 	lookup:		ext3_lookup,		/* BKL held */
 	lookup_raw:	ext3_lookup_raw,	/* BKL held */
 	link:		ext3_link,		/* BKL held */
Index: linux-2.4.24/include/asm-i386/fcntl.h
===================================================================
--- linux-2.4.24.orig/include/asm-i386/fcntl.h	2001-09-18 00:16:30.000000000 +0400
+++ linux-2.4.24/include/asm-i386/fcntl.h	2004-08-03 01:20:55.000000000 +0400
@@ -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-2.4.24/include/linux/ext3_fs.h
===================================================================
--- linux-2.4.24.orig/include/linux/ext3_fs.h	2004-08-02 22:13:12.000000000 +0400
+++ linux-2.4.24/include/linux/ext3_fs.h	2004-08-03 01:03:39.000000000 +0400
@@ -343,6 +343,7 @@
 #define EXT3_MOUNT_ASYNCDEL		0x20000 /* Delayed deletion */
 #define EXT3_MOUNT_EXTENTS		0x100000/* Extents support */
 #define EXT3_MOUNT_EXTDEBUG		0x200000/* Extents debug */
+#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 _LINUX_EXT2_FS_H
@@ -482,6 +483,8 @@
 
 #define EXT3_GOOD_OLD_INODE_SIZE 128
 
+#define EXT3_S_INRESERVE	01000000
+
 /*
  * Feature set definitions
  */