Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm

* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm: (24 commits)
  dm crypt: add documentation
  dm: remove md argument from specific_minor
  dm table: remove unused dm_create_error_table
  dm table: drop void suspend_targets return
  dm: unplug queues in threads
  dm raid1: use timer
  dm: move include files
  dm kcopyd: rename
  dm: expose macros
  dm kcopyd: remove redundant client counting
  dm kcopyd: private mempool
  dm kcopyd: per device
  dm log: make module use tracking internal
  dm log: move register functions
  dm log: clean interface
  dm kcopyd: clean interface
  dm io: clean interface
  dm io: rename error to error_bits
  dm snapshot: store pointer to target instance
  dm log: move dirty region log code into separate module
  ...

Documentation/device-mapper/dm-crypt.txt

@@ -0,0 +1,52 @@
+dm-crypt
+=========
+
+Device-Mapper's "crypt" target provides transparent encryption of block devices
+using the kernel crypto API.
+
+Parameters: <cipher> <key> <iv_offset> <device path> <offset>
+
+<cipher>
+    Encryption cipher and an optional IV generation mode.
+    (In format cipher-chainmode-ivopts:ivmode).
+    Examples:
+       des
+       aes-cbc-essiv:sha256
+       twofish-ecb
+
+    /proc/crypto contains supported crypto modes
+
+<key>
+    Key used for encryption. It is encoded as a hexadecimal number.
+    You can only use key sizes that are valid for the selected cipher.
+
+<iv_offset>
+    The IV offset is a sector count that is added to the sector number
+    before creating the IV.
+
+<device path>
+    This is the device that is going to be used as backend and contains the
+    encrypted data.  You can specify it as a path like /dev/xxx or a device
+    number <major>:<minor>.
+
+<offset>
+    Starting sector within the device where the encrypted data begins.
+
+Example scripts
+===============
+LUKS (Linux Unified Key Setup) is now the preferred way to set up disk
+encryption with dm-crypt using the 'cryptsetup' utility, see
+http://luks.endorphin.org/
+
+[[
+#!/bin/sh
+# Create a crypt device using dmsetup
+dmsetup create crypt1 --table "0 `blockdev --getsize $1` crypt aes-cbc-essiv:sha256 babebabebabebabebabebabebabebabe 0 $1 0"
+]]
+
+[[
+#!/bin/sh
+# Create a crypt device using cryptsetup and LUKS header with default cipher
+cryptsetup luksFormat $1
+cryptsetup luksOpen $1 crypt1
+]]

drivers/md/Makefile

@@ -3,10 +3,10 @@
 #
 
 dm-mod-objs	:= dm.o dm-table.o dm-target.o dm-linear.o dm-stripe.o \
-		   dm-ioctl.o dm-io.o kcopyd.o
+		   dm-ioctl.o dm-io.o dm-kcopyd.o
 dm-multipath-objs := dm-hw-handler.o dm-path-selector.o dm-mpath.o
 dm-snapshot-objs := dm-snap.o dm-exception-store.o
-dm-mirror-objs	:= dm-log.o dm-raid1.o
+dm-mirror-objs	:= dm-raid1.o
 dm-rdac-objs	:= dm-mpath-rdac.o
 dm-hp-sw-objs	:= dm-mpath-hp-sw.o
 md-mod-objs     := md.o bitmap.o
@@ -39,7 +39,7 @@ obj-$(CONFIG_DM_MULTIPATH_EMC)	+= dm-emc.o
 obj-$(CONFIG_DM_MULTIPATH_HP)	+= dm-hp-sw.o
 obj-$(CONFIG_DM_MULTIPATH_RDAC)	+= dm-rdac.o
 obj-$(CONFIG_DM_SNAPSHOT)	+= dm-snapshot.o
-obj-$(CONFIG_DM_MIRROR)		+= dm-mirror.o
+obj-$(CONFIG_DM_MIRROR)		+= dm-mirror.o dm-log.o
 obj-$(CONFIG_DM_ZERO)		+= dm-zero.o
 
 quiet_cmd_unroll = UNROLL  $@

drivers/md/dm-exception-store.c

@@ -9,13 +9,13 @@
 
 #include "dm.h"
 #include "dm-snap.h"
-#include "dm-io.h"
-#include "kcopyd.h"
 
 #include <linux/mm.h>
 #include <linux/pagemap.h>
 #include <linux/vmalloc.h>
 #include <linux/slab.h>
+#include <linux/dm-io.h>
+#include <linux/dm-kcopyd.h>
 
 #define DM_MSG_PREFIX "snapshots"
 #define DM_CHUNK_SIZE_DEFAULT_SECTORS 32	/* 16KB */
@@ -131,7 +131,7 @@ struct pstore {
 
 static unsigned sectors_to_pages(unsigned sectors)
 {
-	return sectors / (PAGE_SIZE >> 9);
+	return DIV_ROUND_UP(sectors, PAGE_SIZE >> 9);
 }
 
 static int alloc_area(struct pstore *ps)
@@ -159,7 +159,7 @@ static void free_area(struct pstore *ps)
 }
 
 struct mdata_req {
-	struct io_region *where;
+	struct dm_io_region *where;
 	struct dm_io_request *io_req;
 	struct work_struct work;
 	int result;
@@ -177,7 +177,7 @@ static void do_metadata(struct work_struct *work)
  */
 static int chunk_io(struct pstore *ps, uint32_t chunk, int rw, int metadata)
 {
-	struct io_region where = {
+	struct dm_io_region where = {
 		.bdev = ps->snap->cow->bdev,
 		.sector = ps->snap->chunk_size * chunk,
 		.count = ps->snap->chunk_size,

drivers/md/dm-io.c

@@ -5,13 +5,14 @@
  * This file is released under the GPL.
  */
 
-#include "dm-io.h"
+#include "dm.h"
 
 #include <linux/bio.h>
 #include <linux/mempool.h>
 #include <linux/module.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
+#include <linux/dm-io.h>
 
 struct dm_io_client {
 	mempool_t *pool;
@@ -20,7 +21,7 @@ struct dm_io_client {
 
 /* FIXME: can we shrink this ? */
 struct io {
-	unsigned long error;
+	unsigned long error_bits;
 	atomic_t count;
 	struct task_struct *sleeper;
 	struct dm_io_client *client;
@@ -107,14 +108,14 @@ static inline unsigned bio_get_region(struct bio *bio)
 static void dec_count(struct io *io, unsigned int region, int error)
 {
 	if (error)
-		set_bit(region, &io->error);
+		set_bit(region, &io->error_bits);
 
 	if (atomic_dec_and_test(&io->count)) {
 		if (io->sleeper)
 			wake_up_process(io->sleeper);
 
 		else {
-			unsigned long r = io->error;
+			unsigned long r = io->error_bits;
 			io_notify_fn fn = io->callback;
 			void *context = io->context;
 
@@ -271,7 +272,7 @@ static void km_dp_init(struct dpages *dp, void *data)
 /*-----------------------------------------------------------------
  * IO routines that accept a list of pages.
  *---------------------------------------------------------------*/
-static void do_region(int rw, unsigned int region, struct io_region *where,
+static void do_region(int rw, unsigned region, struct dm_io_region *where,
 		      struct dpages *dp, struct io *io)
 {
 	struct bio *bio;
@@ -320,7 +321,7 @@ static void do_region(int rw, unsigned int region, struct io_region *where,
 }
 
 static void dispatch_io(int rw, unsigned int num_regions,
-			struct io_region *where, struct dpages *dp,
+			struct dm_io_region *where, struct dpages *dp,
 			struct io *io, int sync)
 {
 	int i;
@@ -347,17 +348,17 @@ static void dispatch_io(int rw, unsigned int num_regions,
 }
 
 static int sync_io(struct dm_io_client *client, unsigned int num_regions,
-		   struct io_region *where, int rw, struct dpages *dp,
+		   struct dm_io_region *where, int rw, struct dpages *dp,
 		   unsigned long *error_bits)
 {
 	struct io io;
 
-	if (num_regions > 1 && rw != WRITE) {
+	if (num_regions > 1 && (rw & RW_MASK) != WRITE) {
 		WARN_ON(1);
 		return -EIO;
 	}
 
-	io.error = 0;
+	io.error_bits = 0;
 	atomic_set(&io.count, 1); /* see dispatch_io() */
 	io.sleeper = current;
 	io.client = client;
@@ -378,25 +379,25 @@ static int sync_io(struct dm_io_client *client, unsigned int num_regions,
 		return -EINTR;
 
 	if (error_bits)
-		*error_bits = io.error;
+		*error_bits = io.error_bits;
 
-	return io.error ? -EIO : 0;
+	return io.error_bits ? -EIO : 0;
 }
 
 static int async_io(struct dm_io_client *client, unsigned int num_regions,
-		    struct io_region *where, int rw, struct dpages *dp,
+		    struct dm_io_region *where, int rw, struct dpages *dp,
 		    io_notify_fn fn, void *context)
 {
 	struct io *io;
 
-	if (num_regions > 1 && rw != WRITE) {
+	if (num_regions > 1 && (rw & RW_MASK) != WRITE) {
 		WARN_ON(1);
 		fn(1, context);
 		return -EIO;
 	}
 
 	io = mempool_alloc(client->pool, GFP_NOIO);
-	io->error = 0;
+	io->error_bits = 0;
 	atomic_set(&io->count, 1); /* see dispatch_io() */
 	io->sleeper = NULL;
 	io->client = client;
@@ -435,10 +436,15 @@ static int dp_init(struct dm_io_request *io_req, struct dpages *dp)
 }
 
 /*
- * New collapsed (a)synchronous interface
+ * New collapsed (a)synchronous interface.
+ *
+ * If the IO is asynchronous (i.e. it has notify.fn), you must either unplug
+ * the queue with blk_unplug() some time later or set the BIO_RW_SYNC bit in
+ * io_req->bi_rw. If you fail to do one of these, the IO will be submitted to
+ * the disk after q->unplug_delay, which defaults to 3ms in blk-settings.c.
  */
 int dm_io(struct dm_io_request *io_req, unsigned num_regions,
-	  struct io_region *where, unsigned long *sync_error_bits)
+	  struct dm_io_region *where, unsigned long *sync_error_bits)
 {
 	int r;
 	struct dpages dp;