Commit 1e337a1e authored by Seth Howell's avatar Seth Howell Committed by Tomasz Zawadzki
Browse files

nvmf/subsystem: New path when we fail to change the subsystem state. 



This can happen and we should be prepared for it.

Maybe fixes: issue #1416

Signed-off-by: default avatarSeth Howell <seth.howell@intel.com>
Change-Id: I77f48dbcabf702f88df56ad7e866bbcb830fc239
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/3393


Community-CI: Mellanox Build Bot
Community-CI: Broadcom CI
Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarMichael Haeuptle <michaelhaeuptle@gmail.com>
Reviewed-by: default avatarAleksey Marchuk <alexeymar@mellanox.com>
parent d8190d02

lib/nvmf/nvmf.c

+6 −2
Original line number Diff line number Diff line
@@ -1386,7 +1386,9 @@ nvmf_poll_group_pause_subsystem(struct spdk_nvmf_poll_group *group, 
		goto fini;

	}



	assert(sgroup->state == SPDK_NVMF_SUBSYSTEM_ACTIVE);

	if (sgroup->state == SPDK_NVMF_SUBSYSTEM_PAUSED) {

		goto fini;

	}

	sgroup->state = SPDK_NVMF_SUBSYSTEM_PAUSING;



	if (sgroup->io_outstanding > 0) {
@@ -1419,7 +1421,9 @@ nvmf_poll_group_resume_subsystem(struct spdk_nvmf_poll_group *group, 


	sgroup = &group->sgroups[subsystem->id];



	assert(sgroup->state == SPDK_NVMF_SUBSYSTEM_PAUSED);

	if (sgroup->state == SPDK_NVMF_SUBSYSTEM_ACTIVE) {

		goto fini;

	}



	rc = poll_group_update_subsystem(group, subsystem);

	if (rc) {

lib/nvmf/subsystem.c

+46 −3
Original line number Diff line number Diff line
@@ -232,6 +232,8 @@ nvmf_valid_nqn(const char *nqn) 
	return true;

}



static void subsystem_state_change_on_pg(struct spdk_io_channel_iter *i);



struct spdk_nvmf_subsystem *

spdk_nvmf_subsystem_create(struct spdk_nvmf_tgt *tgt,

			   const char *nqn,
@@ -442,6 +444,11 @@ nvmf_subsystem_set_state(struct spdk_nvmf_subsystem *subsystem, 
		    state == SPDK_NVMF_SUBSYSTEM_DEACTIVATING) {

			expected_old_state = SPDK_NVMF_SUBSYSTEM_ACTIVATING;

		}

		/* This is for the case when resuming the subsystem fails. */

		if (actual_old_state == SPDK_NVMF_SUBSYSTEM_RESUMING &&

		    state == SPDK_NVMF_SUBSYSTEM_PAUSING) {

			expected_old_state = SPDK_NVMF_SUBSYSTEM_RESUMING;

		}

		actual_old_state = expected_old_state;

		__atomic_compare_exchange_n(&subsystem->state, &actual_old_state, state, false,

					    __ATOMIC_RELAXED, __ATOMIC_RELAXED);
@@ -453,16 +460,36 @@ nvmf_subsystem_set_state(struct spdk_nvmf_subsystem *subsystem, 
struct subsystem_state_change_ctx {

	struct spdk_nvmf_subsystem *subsystem;



	enum spdk_nvmf_subsystem_state original_state;



	enum spdk_nvmf_subsystem_state requested_state;



	spdk_nvmf_subsystem_state_change_done cb_fn;

	void *cb_arg;

};



static void

subsystem_state_change_revert_done(struct spdk_io_channel_iter *i, int status)

{

	struct subsystem_state_change_ctx *ctx = spdk_io_channel_iter_get_ctx(i);



	/* Nothing to be done here if the state setting fails, we are just screwed. */

	if (nvmf_subsystem_set_state(ctx->subsystem, ctx->requested_state)) {

		SPDK_ERRLOG("Unable to revert the subsystem state after operation failure.\n");

	}



	if (ctx->cb_fn) {

		/* return a failure here. This function only exists in an error path. */

		ctx->cb_fn(ctx->subsystem, ctx->cb_arg, -1);

	}

	free(ctx);

}



static void

subsystem_state_change_done(struct spdk_io_channel_iter *i, int status)

{

	struct subsystem_state_change_ctx *ctx = spdk_io_channel_iter_get_ctx(i);

	enum spdk_nvmf_subsystem_state intermediate_state;



	if (status == 0) {

		status = nvmf_subsystem_set_state(ctx->subsystem, ctx->requested_state);
@@ -471,6 +498,23 @@ subsystem_state_change_done(struct spdk_io_channel_iter *i, int status) 
		}

	}



	if (status) {

		intermediate_state = nvmf_subsystem_get_intermediate_state(ctx->requested_state,

				     ctx->original_state);

		assert(intermediate_state != SPDK_NVMF_SUBSYSTEM_NUM_STATES);



		if (nvmf_subsystem_set_state(ctx->subsystem, intermediate_state)) {

			goto out;

		}

		ctx->requested_state = ctx->original_state;

		spdk_for_each_channel(ctx->subsystem->tgt,

				      subsystem_state_change_on_pg,

				      ctx,

				      subsystem_state_change_revert_done);

		return;

	}



out:

	if (ctx->cb_fn) {

		ctx->cb_fn(ctx->subsystem, ctx->cb_arg, status);

	}
@@ -526,15 +570,14 @@ nvmf_subsystem_state_change(struct spdk_nvmf_subsystem *subsystem, 
	int rc;



	intermediate_state = nvmf_subsystem_get_intermediate_state(subsystem->state, requested_state);

	if (intermediate_state == SPDK_NVMF_SUBSYSTEM_NUM_STATES) {

		return -EINVAL;

	}

	assert(intermediate_state != SPDK_NVMF_SUBSYSTEM_NUM_STATES);



	ctx = calloc(1, sizeof(*ctx));

	if (!ctx) {

		return -ENOMEM;

	}



	ctx->original_state = subsystem->state;

	rc = nvmf_subsystem_set_state(subsystem, intermediate_state);

	if (rc) {

		free(ctx);