/*

 * CDDL HEADER START

 *

 * The contents of this file are subject to the terms of the

 * Common Development and Distribution License (the "License").

 * You may not use this file except in compliance with the License.

 *

 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

 * or http://www.opensolaris.org/os/licensing.

 * See the License for the specific language governing permissions

 * and limitations under the License.

 *

 * When distributing Covered Code, include this CDDL HEADER in each

 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.

 * If applicable, add the following below this CDDL HEADER, with the

 * fields enclosed by brackets "[]" replaced with your own identifying

 * information: Portions Copyright [yyyy] [name of copyright owner]

 *

 * CDDL HEADER END

 */

/*

 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.

 * Use is subject to license terms.

 */

#pragma ident	"%Z%%M%	%I%	%E% SMI"

#include <sys/spa.h>

#include <sys/spa_impl.h>

#include <sys/vdev.h>

#include <sys/vdev_impl.h>

#include <sys/zio.h>

#include <sys/fm/fs/zfs.h>

#include <sys/fm/protocol.h>

#include <sys/fm/util.h>

#include <sys/sysevent.h>

/*

 * This general routine is responsible for generating all the different ZFS

 * ereports.  The payload is dependent on the class, and which arguments are

 * supplied to the function:

 *

 * 	EREPORT			POOL	VDEV	IO

 * 	block			X	X	X

 * 	data			X		X

 * 	device			X	X

 * 	pool			X

 *

 * If we are in a loading state, all errors are chained together by the same

 * SPA-wide ENA.

 *

 * For isolated I/O requests, we get the ENA from the zio_t. The propagation

 * gets very complicated due to RAID-Z, gang blocks, and vdev caching.  We want

 * to chain together all ereports associated with a logical piece of data.  For

 * read I/Os, there  are basically three 'types' of I/O, which form a roughly

 * layered diagram:

 *

 *      +---------------+

 * 	| Aggregate I/O |	No associated logical data or device

 * 	+---------------+

 *              |

 *              V

 * 	+---------------+	Reads associated with a piece of logical data.

 * 	|   Read I/O    |	This includes reads on behalf of RAID-Z,

 * 	+---------------+       mirrors, gang blocks, retries, etc.

 *              |

 *              V

 * 	+---------------+	Reads associated with a particular device, but

 * 	| Physical I/O  |	no logical data.  Issued as part of vdev caching

 * 	+---------------+	and I/O aggregation.

 *

 * Note that 'physical I/O' here is not the same terminology as used in the rest

 * of ZIO.  Typically, 'physical I/O' simply means that there is no attached

 * blockpointer.  But I/O with no associated block pointer can still be related

 * to a logical piece of data (i.e. RAID-Z requests).

 *

 * Purely physical I/O always have unique ENAs.  They are not related to a

 * particular piece of logical data, and therefore cannot be chained together.

 * We still generate an ereport, but the DE doesn't correlate it with any

 * logical piece of data.  When such an I/O fails, the delegated I/O requests

 * will issue a retry, which will trigger the 'real' ereport with the correct

 * ENA.

 *

 * We keep track of the ENA for a ZIO chain through the 'io_logical' member.

 * When a new logical I/O is issued, we set this to point to itself.  Child I/Os

 * then inherit this pointer, so that when it is first set subsequent failures

 * will use the same ENA.  If a physical I/O is issued (by passing the

 * ZIO_FLAG_NOBOOKMARK flag), then this pointer is reset, guaranteeing that a

 * unique ENA will be generated.  For an aggregate I/O, this pointer is set to

 * NULL, and no ereport will be generated (since it doesn't actually correspond

 * to any particular device or piece of data).

 */

void

zfs_ereport_post(const char *subclass, spa_t *spa, vdev_t *vd, zio_t *zio,

    uint64_t stateoroffset, uint64_t size)

{

#ifdef _KERNEL

	nvlist_t *ereport, *detector;

	uint64_t ena;

	char class[64];

	/*

	 * If we are doing a spa_tryimport(), ignore errors.

	 */

	if (spa->spa_load_state == SPA_LOAD_TRYIMPORT)

		return;

	/*

	 * If we are in the middle of opening a pool, and the previous attempt

	 * failed, don't bother logging any new ereports - we're just going to

	 * get the same diagnosis anyway.

	 */

	if (spa->spa_load_state != SPA_LOAD_NONE &&

	    spa->spa_last_open_failed)

		return;

	/*

	 * Ignore any errors from I/Os that we are going to retry anyway - we

	 * only generate errors from the final failure.  Checksum errors are

	 * generated after the pipeline stage responsible for retrying the I/O

	 * (VDEV_IO_ASSESS), so this only applies to standard I/O errors.

	 */

	if (zio && zio_should_retry(zio) && zio->io_error != ECKSUM)

		return;

	/*

	 * If this is not a read or write zio, ignore the error.  This can occur

	 * if the DKIOCFLUSHWRITECACHE ioctl fails.

	 */

	if (zio && zio->io_type != ZIO_TYPE_READ &&

	    zio->io_type != ZIO_TYPE_WRITE)

		return;

	if ((ereport = fm_nvlist_create(NULL)) == NULL)

		return;

	if ((detector = fm_nvlist_create(NULL)) == NULL) {

		fm_nvlist_destroy(ereport, FM_NVA_FREE);

		return;

	}

	/*

	 * Serialize ereport generation

	 */

	mutex_enter(&spa->spa_errlist_lock);

	/*

	 * Determine the ENA to use for this event.  If we are in a loading

	 * state, use a SPA-wide ENA.  Otherwise, if we are in an I/O state, use

	 * a root zio-wide ENA.  Otherwise, simply use a unique ENA.

	 */

	if (spa->spa_load_state != SPA_LOAD_NONE) {

		if (spa->spa_ena == 0)

			spa->spa_ena = fm_ena_generate(0, FM_ENA_FMT1);

		ena = spa->spa_ena;

	} else if (zio != NULL && zio->io_logical != NULL) {

		if (zio->io_logical->io_ena == 0)

			zio->io_logical->io_ena =

			    fm_ena_generate(0, FM_ENA_FMT1);

		ena = zio->io_logical->io_ena;

	} else {

		ena = fm_ena_generate(0, FM_ENA_FMT1);

	}

	/*

	 * Construct the full class, detector, and other standard FMA fields.

	 */

	(void) snprintf(class, sizeof (class), "%s.%s",

	    ZFS_ERROR_CLASS, subclass);

	fm_fmri_zfs_set(detector, FM_ZFS_SCHEME_VERSION, spa_guid(spa),

	    vd != NULL ? vd->vdev_guid : 0);

	fm_ereport_set(ereport, FM_EREPORT_VERSION, class, ena, detector, NULL);

	/*

	 * Construct the per-ereport payload, depending on which parameters are

	 * passed in.

	 */

	/*

	 * Generic payload members common to all ereports.

	 *

	 * The direct reference to spa_name is used rather than spa_name()

	 * because of the asynchronous nature of the zio pipeline.  spa_name()

	 * asserts that the config lock is held in some form.  This is always

	 * the case in I/O context, but because the check for RW_WRITER compares

	 * against 'curthread', we may be in an asynchronous context and blow

	 * this assert.  Rather than loosen this assert, we acknowledge that all

	 * contexts in which this function is called (pool open, I/O) are safe,

	 * and dereference the name directly.

	 */

	fm_payload_set(ereport, FM_EREPORT_PAYLOAD_ZFS_POOL,

	    DATA_TYPE_STRING, spa->spa_name, FM_EREPORT_PAYLOAD_ZFS_POOL_GUID,

	    DATA_TYPE_UINT64, spa_guid(spa),

	    FM_EREPORT_PAYLOAD_ZFS_POOL_CONTEXT, DATA_TYPE_INT32,

	    spa->spa_load_state, NULL);

	if (vd != NULL) {

		vdev_t *pvd = vd->vdev_parent;

		fm_payload_set(ereport, FM_EREPORT_PAYLOAD_ZFS_VDEV_GUID,

		    DATA_TYPE_UINT64, vd->vdev_guid,

		    FM_EREPORT_PAYLOAD_ZFS_VDEV_TYPE,

		    DATA_TYPE_STRING, vd->vdev_ops->vdev_op_type, NULL);

		if (vd->vdev_path)

			fm_payload_set(ereport,

			    FM_EREPORT_PAYLOAD_ZFS_VDEV_PATH,

			    DATA_TYPE_STRING, vd->vdev_path, NULL);

		if (vd->vdev_devid)

			fm_payload_set(ereport,

			    FM_EREPORT_PAYLOAD_ZFS_VDEV_DEVID,

			    DATA_TYPE_STRING, vd->vdev_devid, NULL);

		if (pvd != NULL) {

			fm_payload_set(ereport,

			    FM_EREPORT_PAYLOAD_ZFS_PARENT_GUID,

			    DATA_TYPE_UINT64, pvd->vdev_guid,

			    FM_EREPORT_PAYLOAD_ZFS_PARENT_TYPE,

			    DATA_TYPE_STRING, pvd->vdev_ops->vdev_op_type,

			    NULL);

			if (pvd->vdev_path)

				fm_payload_set(ereport,

				    FM_EREPORT_PAYLOAD_ZFS_PARENT_PATH,

			if (pvd->vdev_devid)

				fm_payload_set(ereport,

				    FM_EREPORT_PAYLOAD_ZFS_PARENT_DEVID,

				    DATA_TYPE_STRING, pvd->vdev_devid, NULL);

		}

	}

	if (zio != NULL) {

		/*

		 * Payload common to all I/Os.

		 */

		fm_payload_set(ereport, FM_EREPORT_PAYLOAD_ZFS_ZIO_ERR,

		    DATA_TYPE_INT32, zio->io_error, NULL);

		/*

		 * If the 'size' parameter is non-zero, it indicates this is a

		 * RAID-Z or other I/O where the physical offset and length are

		 * provided for us, instead of within the zio_t.

		 */

		if (vd != NULL) {

			if (size)

				fm_payload_set(ereport,

				    FM_EREPORT_PAYLOAD_ZFS_ZIO_OFFSET,

				    DATA_TYPE_UINT64, stateoroffset,

				    FM_EREPORT_PAYLOAD_ZFS_ZIO_SIZE,

				    DATA_TYPE_UINT64, size, NULL);

			else

				fm_payload_set(ereport,

				    FM_EREPORT_PAYLOAD_ZFS_ZIO_OFFSET,

				    DATA_TYPE_UINT64, zio->io_offset,

				    FM_EREPORT_PAYLOAD_ZFS_ZIO_SIZE,

				    DATA_TYPE_UINT64, zio->io_size, NULL);

		}

		/*

		 * Payload for I/Os with corresponding logical information.

		 */

		if (zio->io_logical != NULL)

			fm_payload_set(ereport,

			    FM_EREPORT_PAYLOAD_ZFS_ZIO_OBJECT,

			    DATA_TYPE_UINT64,

			    zio->io_logical->io_bookmark.zb_object,

			    FM_EREPORT_PAYLOAD_ZFS_ZIO_LEVEL,

			    zio->io_logical->io_bookmark.zb_level,

			    FM_EREPORT_PAYLOAD_ZFS_ZIO_BLKID,

			    DATA_TYPE_UINT64,

			    zio->io_logical->io_bookmark.zb_blkid, NULL);

	} else if (vd != NULL) {

		/*

		 * If we have a vdev but no zio, this is a device fault, and the

		 * 'stateoroffset' parameter indicates the previous state of the

		 * vdev.

		 */

		fm_payload_set(ereport,

		    FM_EREPORT_PAYLOAD_ZFS_PREV_STATE,

		    DATA_TYPE_UINT64, stateoroffset, NULL);

	}

	mutex_exit(&spa->spa_errlist_lock);

	fm_ereport_post(ereport, EVCH_SLEEP);

	fm_nvlist_destroy(ereport, FM_NVA_FREE);

	fm_nvlist_destroy(detector, FM_NVA_FREE);

#endif

}

static void

zfs_post_common(spa_t *spa, vdev_t *vd, const char *name)

{

#ifdef _KERNEL

	nvlist_t *resource;

	char class[64];

	if ((resource = fm_nvlist_create(NULL)) == NULL)

		return;

	(void) snprintf(class, sizeof (class), "%s.%s.%s", FM_RSRC_RESOURCE,

	    ZFS_ERROR_CLASS, name);

	VERIFY(nvlist_add_uint8(resource, FM_VERSION, FM_RSRC_VERSION) == 0);

	VERIFY(nvlist_add_string(resource, FM_CLASS, class) == 0);

	VERIFY(nvlist_add_uint64(resource,

	    FM_EREPORT_PAYLOAD_ZFS_POOL_GUID, spa_guid(spa)) == 0);

	if (vd)

		VERIFY(nvlist_add_uint64(resource,

		    FM_EREPORT_PAYLOAD_ZFS_VDEV_GUID, vd->vdev_guid) == 0);

	fm_ereport_post(resource, EVCH_SLEEP);

	fm_nvlist_destroy(resource, FM_NVA_FREE);

#endif

}

/*

 * The 'resource.fs.zfs.ok' event is an internal signal that the associated

 * resource (pool or disk) has been identified by ZFS as healthy.  This will

 * then trigger the DE to close the associated case, if any.

 */

void

zfs_post_ok(spa_t *spa, vdev_t *vd)

{

	zfs_post_common(spa, vd, FM_RESOURCE_OK);

}

/*

 * The 'resource.fs.zfs.removed' event is an internal signal that the given vdev

 * has been removed from the system.  This will cause the DE to ignore any

 * recent I/O errors, inferring that they are due to the asynchronous device

 * removal.

 */

void

zfs_post_remove(spa_t *spa, vdev_t *vd)

{

	zfs_post_common(spa, vd, FM_RESOURCE_REMOVED);

}

/*

 * The 'resource.fs.zfs.autoreplace' event is an internal signal that the pool

 * has the 'autoreplace' property set, and therefore any broken vdevs will be

 * handled by higher level logic, and no vdev fault should be generated.

 */

void

zfs_post_autoreplace(spa_t *spa, vdev_t *vd)

{

	zfs_post_common(spa, vd, FM_RESOURCE_AUTOREPLACE);

}