dm: move include files

Publish the dm-io, dm-log and dm-kcopyd headers in include/linux.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>

3 files changed, 263 insertions, 0 deletions

diff --git a/include/linux/dm-dirty-log.h b/include/linux/dm-dirty-log.h
new file mode 100644
index 000000000000..600c5fb2daad
--- /dev/null
+++ b/include/linux/dm-dirty-log.h
@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2003 Sistina Software
+ * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
+ *
+ * Device-Mapper dirty region log.
+ *
+ * This file is released under the LGPL.
+ */
+
+#ifndef _LINUX_DM_DIRTY_LOG
+#define _LINUX_DM_DIRTY_LOG
+
+#ifdef __KERNEL__
+
+#include <linux/types.h>
+#include <linux/device-mapper.h>
+
+typedef sector_t region_t;
+
+struct dm_dirty_log_type;
+
+struct dm_dirty_log {
+        struct dm_dirty_log_type *type;
+        void *context;
+};
+
+struct dm_dirty_log_type {
+        const char *name;
+        struct module *module;
+
+        int (*ctr)(struct dm_dirty_log *log, struct dm_target *ti,
+                   unsigned argc, char **argv);
+        void (*dtr)(struct dm_dirty_log *log);
+
+        /*
+         * There are times when we don't want the log to touch
+         * the disk.
+         */
+        int (*presuspend)(struct dm_dirty_log *log);
+        int (*postsuspend)(struct dm_dirty_log *log);
+        int (*resume)(struct dm_dirty_log *log);
+
+        /*
+         * Retrieves the smallest size of region that the log can
+         * deal with.
+         */
+        uint32_t (*get_region_size)(struct dm_dirty_log *log);
+
+        /*
+         * A predicate to say whether a region is clean or not.
+         * May block.
+         */
+        int (*is_clean)(struct dm_dirty_log *log, region_t region);
+
+        /*
+         *  Returns: 0, 1, -EWOULDBLOCK, < 0
+         *
+         * A predicate function to check the area given by
+         * [sector, sector + len) is in sync.
+         *
+         * If -EWOULDBLOCK is returned the state of the region is
+         * unknown, typically this will result in a read being
+         * passed to a daemon to deal with, since a daemon is
+         * allowed to block.
+         */
+        int (*in_sync)(struct dm_dirty_log *log, region_t region,
+                       int can_block);
+
+        /*
+         * Flush the current log state (eg, to disk).  This
+         * function may block.
+         */
+        int (*flush)(struct dm_dirty_log *log);
+
+        /*
+         * Mark an area as clean or dirty.  These functions may
+         * block, though for performance reasons blocking should
+         * be extremely rare (eg, allocating another chunk of
+         * memory for some reason).
+         */
+        void (*mark_region)(struct dm_dirty_log *log, region_t region);
+        void (*clear_region)(struct dm_dirty_log *log, region_t region);
+
+        /*
+         * Returns: <0 (error), 0 (no region), 1 (region)
+         *
+         * The mirrord will need perform recovery on regions of
+         * the mirror that are in the NOSYNC state.  This
+         * function asks the log to tell the caller about the
+         * next region that this machine should recover.
+         *
+         * Do not confuse this function with 'in_sync()', one
+         * tells you if an area is synchronised, the other
+         * assigns recovery work.
+        */
+        int (*get_resync_work)(struct dm_dirty_log *log, region_t *region);
+
+        /*
+         * This notifies the log that the resync status of a region
+         * has changed.  It also clears the region from the recovering
+         * list (if present).
+         */
+        void (*set_region_sync)(struct dm_dirty_log *log,
+                                region_t region, int in_sync);
+
+        /*
+         * Returns the number of regions that are in sync.
+         */
+        region_t (*get_sync_count)(struct dm_dirty_log *log);
+
+        /*
+         * Support function for mirror status requests.
+         */
+        int (*status)(struct dm_dirty_log *log, status_type_t status_type,
+                      char *result, unsigned maxlen);
+};
+
+int dm_dirty_log_type_register(struct dm_dirty_log_type *type);
+int dm_dirty_log_type_unregister(struct dm_dirty_log_type *type);
+
+/*
+ * Make sure you use these two functions, rather than calling
+ * type->constructor/destructor() directly.
+ */
+struct dm_dirty_log *dm_dirty_log_create(const char *type_name,
+                                         struct dm_target *ti,
+                                         unsigned argc, char **argv);
+void dm_dirty_log_destroy(struct dm_dirty_log *log);
+
+#endif  /* __KERNEL__ */
+#endif  /* _LINUX_DM_DIRTY_LOG_H */
diff --git a/include/linux/dm-io.h b/include/linux/dm-io.h
new file mode 100644
index 000000000000..b6bf17ee2f61
--- /dev/null
+++ b/include/linux/dm-io.h
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2003 Sistina Software
+ * Copyright (C) 2004 - 2008 Red Hat, Inc. All rights reserved.
+ *
+ * Device-Mapper low-level I/O.
+ *
+ * This file is released under the GPL.
+ */
+
+#ifndef _LINUX_DM_IO_H
+#define _LINUX_DM_IO_H
+
+#ifdef __KERNEL__
+
+#include <linux/types.h>
+
+struct dm_io_region {
+        struct block_device *bdev;
+        sector_t sector;
+        sector_t count;         /* If this is zero the region is ignored. */
+};
+
+struct page_list {
+        struct page_list *next;
+        struct page *page;
+};
+
+typedef void (*io_notify_fn)(unsigned long error, void *context);
+
+enum dm_io_mem_type {
+        DM_IO_PAGE_LIST,/* Page list */
+        DM_IO_BVEC,     /* Bio vector */
+        DM_IO_VMA,      /* Virtual memory area */
+        DM_IO_KMEM,     /* Kernel memory */
+};
+
+struct dm_io_memory {
+        enum dm_io_mem_type type;
+
+        union {
+                struct page_list *pl;
+                struct bio_vec *bvec;
+                void *vma;
+                void *addr;
+        } ptr;
+
+        unsigned offset;
+};
+
+struct dm_io_notify {
+        io_notify_fn fn;        /* Callback for asynchronous requests */
+        void *context;          /* Passed to callback */
+};
+
+/*
+ * IO request structure
+ */
+struct dm_io_client;
+struct dm_io_request {
+        int bi_rw;                      /* READ|WRITE - not READA */
+        struct dm_io_memory mem;        /* Memory to use for io */
+        struct dm_io_notify notify;     /* Synchronous if notify.fn is NULL */
+        struct dm_io_client *client;    /* Client memory handler */
+};
+
+/*
+ * For async io calls, users can alternatively use the dm_io() function below
+ * and dm_io_client_create() to create private mempools for the client.
+ *
+ * Create/destroy may block.
+ */
+struct dm_io_client *dm_io_client_create(unsigned num_pages);
+int dm_io_client_resize(unsigned num_pages, struct dm_io_client *client);
+void dm_io_client_destroy(struct dm_io_client *client);
+
+/*
+ * IO interface using private per-client pools.
+ * Each bit in the optional 'sync_error_bits' bitset indicates whether an
+ * error occurred doing io to the corresponding region.
+ */
+int dm_io(struct dm_io_request *io_req, unsigned num_regions,
+          struct dm_io_region *region, unsigned long *sync_error_bits);
+
+#endif  /* __KERNEL__ */
+#endif  /* _LINUX_DM_IO_H */
diff --git a/include/linux/dm-kcopyd.h b/include/linux/dm-kcopyd.h
new file mode 100644
index 000000000000..5db216311695
--- /dev/null
+++ b/include/linux/dm-kcopyd.h
@@ -0,0 +1,47 @@
+/*
+ * 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;
+int dm_kcopyd_client_create(unsigned num_pages,
+                            struct dm_kcopyd_client **result);
+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);
+
+#endif  /* __KERNEL__ */
+#endif  /* _LINUX_DM_KCOPYD_H */