[RFC,10/46] e2fsck: open io-channel when copying fs

diff --git a/e2fsck/e2fsck.h b/e2fsck/e2fsck.h
index c63b1852..58fb49c5 100644
--- a/e2fsck/e2fsck.h
+++ b/e2fsck/e2fsck.h
@@ -244,6 +244,7 @@  struct e2fsck_struct {
 	ino_t			 free_inodes;
 	int			 mount_flags;
 	int			 openfs_flags;
+	io_manager		 io_manager;
 	blkid_cache		 blkid; /* blkid cache */
 #ifdef HAVE_SETJMP_H
 	jmp_buf			abort_loc;
diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index de56562c..900d6cad 100644
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -2133,7 +2133,37 @@  do {									\
     }									\
 } while (0)
 
-static errcode_t e2fsck_pass1_copy_fs(ext2_filsys dest, ext2_filsys src)
+static errcode_t pass1_open_io_channel(ext2_filsys fs,
+				       const char *io_options,
+				       io_manager manager, int flags)
+{
+	errcode_t	retval;
+	unsigned int	io_flags = 0;
+
+	if (flags & EXT2_FLAG_RW)
+		io_flags |= IO_FLAG_RW;
+	if (flags & EXT2_FLAG_EXCLUSIVE)
+		io_flags |= IO_FLAG_EXCLUSIVE;
+	if (flags & EXT2_FLAG_DIRECT_IO)
+		io_flags |= IO_FLAG_DIRECT_IO;
+	retval = manager->open(fs->device_name, io_flags, &fs->io);
+	if (retval)
+		return retval;
+
+	if (io_options &&
+	    (retval = io_channel_set_options(fs->io, io_options)))
+		goto out_close;
+	fs->image_io = fs->io;
+	fs->io->app_data = fs;
+
+	return 0;
+out_close:
+	io_channel_close(fs->io);
+	return retval;
+}
+
+static errcode_t e2fsck_pass1_copy_fs(ext2_filsys dest, e2fsck_t src_context,
+				      ext2_filsys src)
 {
 	errcode_t	retval;
 
@@ -2171,6 +2201,33 @@  static errcode_t e2fsck_pass1_copy_fs(ext2_filsys dest, ext2_filsys src)
 		ext2fs_badblocks_list_free(src->badblocks);
 		src->badblocks = NULL;
 	}
+
+	/* disable it for now */
+	src_context->openfs_flags &= ~EXT2_FLAG_EXCLUSIVE;
+	retval = pass1_open_io_channel(dest, src_context->io_options,
+				       src_context->io_manager,
+				       src_context->openfs_flags);
+	if (retval)
+		goto out_dblist;
+
+	/* Block size might not be default */
+	io_channel_set_blksize(dest->io, src->io->block_size);
+	ehandler_init(dest->io);
+
+	assert(dest->io->magic == src->io->magic);
+	assert(dest->io->manager == src->io->manager);
+	assert(strcmp(dest->io->name, src->io->name) == 0);
+	assert(dest->io->block_size == src->io->block_size);
+	assert(dest->io->read_error == src->io->read_error);
+	assert(dest->io->write_error == src->io->write_error);
+	assert(dest->io->refcount == src->io->refcount);
+	assert(dest->io->flags == src->io->flags);
+	assert(dest->io->app_data == dest);
+	assert(src->io->app_data == src);
+	assert(dest->io->align == src->io->align);
+
+	/* The data should be written to disk immediately */
+	dest->io->flags |= CHANNEL_FLAGS_WRITETHROUGH;
 	return 0;
 
 out_dblist:
@@ -2181,9 +2238,15 @@  out_dblist:
 
 static int _e2fsck_pass1_merge_fs(ext2_filsys dest, ext2_filsys src)
 {
-	errcode_t	retval = 0;
+	errcode_t retval = 0;
+	io_channel dest_io;
+	io_channel dest_image_io;
 
+	dest_io = dest->io;
+	dest_image_io = dest->image_io;
 	memcpy(dest, src, sizeof(struct struct_ext2_filsys));
+	dest->io = dest_io;
+	dest->image_io = dest_image_io;
 	/*
 	 * PASS1_COPY_FS_BITMAP might return directly from this function,
 	 * so please do NOT leave any garbage behind after returning.
@@ -2204,6 +2267,7 @@  static int _e2fsck_pass1_merge_fs(ext2_filsys dest, ext2_filsys src)
 		if (retval)
 			goto out_dblist;
 	}
+	io_channel_close(src->io);
 	return 0;
 out_dblist:
 	ext2fs_free_dblist(dest->dblist);
@@ -2270,7 +2334,8 @@  static errcode_t e2fsck_pass1_thread_prepare(e2fsck_t global_ctx, e2fsck_t *thre
 		goto out_context;
 	}
 
-	retval = e2fsck_pass1_copy_fs(thread_fs, global_fs);
+	io_channel_flush_cleanup(global_fs->io);
+	retval = e2fsck_pass1_copy_fs(thread_fs, global_ctx, global_fs);
 	if (retval) {
 		com_err(global_ctx->program_name, retval, "while copying fs");
 		goto out_fs;
diff --git a/e2fsck/unix.c b/e2fsck/unix.c
index 8226aff7..fff7376c 100644
--- a/e2fsck/unix.c
+++ b/e2fsck/unix.c
@@ -1524,6 +1524,7 @@  restart:
 	}
 
 	ctx->openfs_flags = flags;
+	ctx->io_manager = io_ptr;
 	retval = try_open_fs(ctx, flags, io_ptr, &fs);
 
 	if (!ctx->superblock && !(ctx->options & E2F_OPT_PREEN) &&
diff --git a/lib/ext2fs/ext2_io.h b/lib/ext2fs/ext2_io.h
index 5540900a..4ad2fec8 100644
--- a/lib/ext2fs/ext2_io.h
+++ b/lib/ext2fs/ext2_io.h
@@ -81,6 +81,7 @@  struct struct_io_manager {
 	errcode_t (*write_blk)(io_channel channel, unsigned long block,
 			       int count, const void *data);
 	errcode_t (*flush)(io_channel channel);
+	errcode_t (*flush_cleanup)(io_channel channel);
 	errcode_t (*write_byte)(io_channel channel, unsigned long offset,
 				int count, const void *data);
 	errcode_t (*set_option)(io_channel channel, const char *option,
@@ -113,6 +114,7 @@  struct struct_io_manager {
 #define io_channel_read_blk(c,b,n,d)	((c)->manager->read_blk((c),b,n,d))
 #define io_channel_write_blk(c,b,n,d)	((c)->manager->write_blk((c),b,n,d))
 #define io_channel_flush(c) 		((c)->manager->flush((c)))
+#define io_channel_flush_cleanup(c) 	((c)->manager->flush_cleanup((c)))
 #define io_channel_bumpcount(c)		((c)->refcount++)
 
 /* io_manager.c */
diff --git a/lib/ext2fs/undo_io.c b/lib/ext2fs/undo_io.c
index 19862414..1391a534 100644
--- a/lib/ext2fs/undo_io.c
+++ b/lib/ext2fs/undo_io.c
@@ -1020,6 +1020,24 @@  static errcode_t undo_flush(io_channel channel)
 	return retval;
 }
 
+/*
+ * Flush data buffers to disk and cleanup the cache.
+ */
+static errcode_t undo_flush_cleanup(io_channel channel)
+{
+	errcode_t	retval = 0;
+	struct undo_private_data *data;
+
+	EXT2_CHECK_MAGIC(channel, EXT2_ET_MAGIC_IO_CHANNEL);
+	data = (struct undo_private_data *) channel->private_data;
+	EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
+
+	if (data->real)
+		retval = io_channel_flush_cleanup(data->real);
+
+	return retval;
+}
+
 static errcode_t undo_set_option(io_channel channel, const char *option,
 				 const char *arg)
 {
@@ -1091,6 +1109,7 @@  static struct struct_io_manager struct_undo_manager = {
 	.read_blk	= undo_read_blk,
 	.write_blk	= undo_write_blk,
 	.flush		= undo_flush,
+	.flush_cleanup	= undo_flush_cleanup,
 	.write_byte	= undo_write_byte,
 	.set_option	= undo_set_option,
 	.get_stats	= undo_get_stats,
diff --git a/lib/ext2fs/unix_io.c b/lib/ext2fs/unix_io.c
index 628e60c3..c9defd4b 100644
--- a/lib/ext2fs/unix_io.c
+++ b/lib/ext2fs/unix_io.c
@@ -1030,9 +1030,9 @@  static errcode_t unix_write_byte(io_channel channel, unsigned long offset,
 }
 
 /*
- * Flush data buffers to disk.
+ * Flush data buffers to disk and invalidate cache if needed
  */
-static errcode_t unix_flush(io_channel channel)
+static errcode_t _unix_flush(io_channel channel, int invalidate)
 {
 	struct unix_private_data *data;
 	errcode_t retval = 0;
@@ -1042,7 +1042,7 @@  static errcode_t unix_flush(io_channel channel)
 	EXT2_CHECK_MAGIC(data, EXT2_ET_MAGIC_UNIX_IO_CHANNEL);
 
 #ifndef NO_IO_CACHE
-	retval = flush_cached_blocks(channel, data, 0);
+	retval = flush_cached_blocks(channel, data, invalidate);
 #endif
 #ifdef HAVE_FSYNC
 	if (!retval && fsync(data->dev) != 0)
@@ -1051,6 +1051,22 @@  static errcode_t unix_flush(io_channel channel)
 	return retval;
 }
 
+/*
+ * Flush data buffers to disk.
+ */
+static errcode_t unix_flush(io_channel channel)
+{
+	return _unix_flush(channel, 0);
+}
+
+/*
+ * Flush data buffers to disk and invalidate cache.
+ */
+static errcode_t unix_flush_cleanup(io_channel channel)
+{
+	return _unix_flush(channel, 1);
+}
+
 static errcode_t unix_set_option(io_channel channel, const char *option,
 				 const char *arg)
 {
@@ -1225,6 +1241,7 @@  static struct struct_io_manager struct_unix_manager = {
 	.discard	= unix_discard,
 	.cache_readahead	= unix_cache_readahead,
 	.zeroout	= unix_zeroout,
+	.flush_cleanup	= unix_flush_cleanup,
 };
 
 io_manager unix_io_manager = &struct_unix_manager;
@@ -1246,6 +1263,7 @@  static struct struct_io_manager struct_unixfd_manager = {
 	.discard	= unix_discard,
 	.cache_readahead	= unix_cache_readahead,
 	.zeroout	= unix_zeroout,
+	.flush_cleanup	= unix_flush_cleanup,
 };
 
 io_manager unixfd_io_manager = &struct_unixfd_manager;