diff options
Diffstat (limited to 'include/linux/dm-kcopyd.h')
-rw-r--r-- | include/linux/dm-kcopyd.h | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/include/linux/dm-kcopyd.h b/include/linux/dm-kcopyd.h new file mode 100644 index 00000000..47d9d376 --- /dev/null +++ b/include/linux/dm-kcopyd.h @@ -0,0 +1,65 @@ +/* + * Copyright (C) 2001 - 2003 Sistina Software + * Copyright (C) 2004 - 2008 Red Hat, Inc. All rights reserved. + * + * kcopyd provides a simple interface for copying an area of one + * block-device to one or more other block-devices, either synchronous + * or with an asynchronous completion notification. + * + * This file is released under the GPL. + */ + +#ifndef _LINUX_DM_KCOPYD_H +#define _LINUX_DM_KCOPYD_H + +#ifdef __KERNEL__ + +#include <linux/dm-io.h> + +/* FIXME: make this configurable */ +#define DM_KCOPYD_MAX_REGIONS 8 + +#define DM_KCOPYD_IGNORE_ERROR 1 + +/* + * To use kcopyd you must first create a dm_kcopyd_client object. + */ +struct dm_kcopyd_client; +struct dm_kcopyd_client *dm_kcopyd_client_create(void); +void dm_kcopyd_client_destroy(struct dm_kcopyd_client *kc); + +/* + * Submit a copy job to kcopyd. This is built on top of the + * previous three fns. + * + * read_err is a boolean, + * write_err is a bitset, with 1 bit for each destination region + */ +typedef void (*dm_kcopyd_notify_fn)(int read_err, unsigned long write_err, + void *context); + +int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from, + unsigned num_dests, struct dm_io_region *dests, + unsigned flags, dm_kcopyd_notify_fn fn, void *context); + +/* + * Prepare a callback and submit it via the kcopyd thread. + * + * dm_kcopyd_prepare_callback allocates a callback structure and returns it. + * It must not be called from interrupt context. + * The returned value should be passed into dm_kcopyd_do_callback. + * + * dm_kcopyd_do_callback submits the callback. + * It may be called from interrupt context. + * The callback is issued from the kcopyd thread. + */ +void *dm_kcopyd_prepare_callback(struct dm_kcopyd_client *kc, + dm_kcopyd_notify_fn fn, void *context); +void dm_kcopyd_do_callback(void *job, int read_err, unsigned long write_err); + +int dm_kcopyd_zero(struct dm_kcopyd_client *kc, + unsigned num_dests, struct dm_io_region *dests, + unsigned flags, dm_kcopyd_notify_fn fn, void *context); + +#endif /* __KERNEL__ */ +#endif /* _LINUX_DM_KCOPYD_H */ |