Commit 2db06132 authored by Jim Harris's avatar Jim Harris
Browse files

bdev: change bdev io_device handle to odd offset 



Many bdev modules create their own bdev structure
with spdk_bdev as the first member.  bdev.c currently
uses the spdk_bdev pointer as its io_device handle,
forcing bdev modules to pick something different.

Change this to use the spdk_bdev pointer + 1 bytes
as its io_device handle.  The actual handle does not
really matter - it just needs to be unique.  This will
simplify bdev module development.

Signed-off-by: default avatarJim Harris <james.r.harris@intel.com>
Change-Id: I8b6da3be9c16c87bc7a393c3a2221c6bae26e0a5

Reviewed-on: https://review.gerrithub.io/400554


Reviewed-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
parent a601c0b2

lib/bdev/bdev.c

+13 −9
Original line number Diff line number Diff line
@@ -153,6 +153,9 @@ struct spdk_bdev_channel { 


};



#define __bdev_to_io_dev(bdev)		(((char *)bdev) + 1)

#define __bdev_from_io_dev(io_dev)	((struct spdk_bdev *)(((char *)io_dev) - 1))



/*

 * Per-module (or per-io_device) channel. Multiple bdevs built on the same io_device

 * will queue here their IO that awaits retry. It makes it posible to retry sending
@@ -872,11 +875,11 @@ spdk_bdev_dump_config_json(struct spdk_bdev *bdev, struct spdk_json_write_ctx *w 
static int

_spdk_bdev_channel_create(struct spdk_bdev_channel *ch, void *io_device)

{

	struct spdk_bdev		*bdev = io_device;

	struct spdk_bdev		*bdev = __bdev_from_io_dev(io_device);

	struct spdk_bdev_mgmt_channel	*mgmt_ch;

	struct spdk_bdev_module_channel	*shared_ch;



	ch->bdev = io_device;

	ch->bdev = bdev;

	ch->channel = bdev->fn_table->get_io_channel(bdev->ctxt);

	if (!ch->channel) {

		return -1;
@@ -1101,7 +1104,7 @@ spdk_bdev_alias_del(struct spdk_bdev *bdev, const char *alias) 
struct spdk_io_channel *

spdk_bdev_get_io_channel(struct spdk_bdev_desc *desc)

{

	return spdk_get_io_channel(desc->bdev);

	return spdk_get_io_channel(__bdev_to_io_dev(desc->bdev));

}



const char *
@@ -1630,7 +1633,7 @@ _spdk_bdev_start_reset(void *ctx) 
{

	struct spdk_bdev_channel *ch = ctx;



	spdk_for_each_channel(ch->bdev, _spdk_bdev_reset_freeze_channel,

	spdk_for_each_channel(__bdev_to_io_dev(ch->bdev), _spdk_bdev_reset_freeze_channel,

			      ch, _spdk_bdev_reset_dev);

}
@@ -1651,7 +1654,7 @@ _spdk_bdev_channel_start_reset(struct spdk_bdev_channel *ch) 
		 *  progress.  We will release the reference when this reset is

		 *  completed.

		 */

		bdev->reset_in_progress->u.reset.ch_ref = spdk_get_io_channel(bdev);

		bdev->reset_in_progress->u.reset.ch_ref = spdk_get_io_channel(__bdev_to_io_dev(bdev));

		_spdk_bdev_start_reset(ch);

	}

	pthread_mutex_unlock(&bdev->mutex);
@@ -1920,8 +1923,8 @@ spdk_bdev_io_complete(struct spdk_bdev_io *bdev_io, enum spdk_bdev_io_status sta 
		pthread_mutex_unlock(&bdev->mutex);



		if (unlock_channels) {

			spdk_for_each_channel(bdev, _spdk_bdev_unfreeze_channel, bdev_io,

					      _spdk_bdev_reset_complete);

			spdk_for_each_channel(__bdev_to_io_dev(bdev), _spdk_bdev_unfreeze_channel,

					      bdev_io, _spdk_bdev_reset_complete);

			return;

		}

	} else {
@@ -2111,7 +2114,8 @@ _spdk_bdev_register(struct spdk_bdev *bdev) 


	bdev->reset_in_progress = NULL;



	spdk_io_device_register(bdev, spdk_bdev_channel_create, spdk_bdev_channel_destroy,

	spdk_io_device_register(__bdev_to_io_dev(bdev),

				spdk_bdev_channel_create, spdk_bdev_channel_destroy,

				sizeof(struct spdk_bdev_channel));



	pthread_mutex_init(&bdev->mutex, NULL);
@@ -2214,7 +2218,7 @@ spdk_bdev_unregister(struct spdk_bdev *bdev, spdk_bdev_unregister_cb cb_fn, void 


	pthread_mutex_destroy(&bdev->mutex);



	spdk_io_device_unregister(bdev, NULL);

	spdk_io_device_unregister(__bdev_to_io_dev(bdev), NULL);



	rc = bdev->fn_table->destruct(bdev->ctxt);

	if (rc < 0) {