fs/zfs/zfs_fm.c

	zfs_fm.c revision 1d7132005da8d75994a6ad204e6ec05ef5ffaa4b
/*
 * 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 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#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 (Error Numeric Association).
 *
 * 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.  For vdev cache fill and queue aggregation 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,
 * and the caller will always retry without caching or queueing anyway).
 */
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;

    if (zio != NULL) {
        /*
         * If this is not a read or write zio, ignore the error.  This
         * can occur if the DKIOCFLUSHWRITECACHE ioctl fails.
         */
        if (zio->io_type != ZIO_TYPE_READ &&
            zio->io_type != ZIO_TYPE_WRITE)
            return;

        /*
         * Ignore any errors from speculative I/Os, as failure is an
         * expected result.
         */
        if (zio->io_flags & ZIO_FLAG_SPECULATIVE)
            return;

        /*
         * If this I/O is not a retry I/O, don't post an ereport.
         * Otherwise, we risk making bad diagnoses based on B_FAILFAST
         * I/Os.
         */
        if (zio->io_error == EIO &&
            !(zio->io_flags & ZIO_FLAG_IO_RETRY))
            return;

        if (vd != NULL) {
            /*
             * If the vdev has already been marked as failing due
             * to a failed probe, then ignore any subsequent I/O
             * errors, as the DE will automatically fault the vdev
             * on the first such failure.  This also catches cases
             * where vdev_remove_wanted is set and the device has
             * not yet been asynchronously placed into the REMOVED
             * state.
             */
            if (zio->io_vd == vd && !vdev_accessible(vd, zio))
                return;

            /*
             * Ignore checksum errors for reads from DTL regions of
             * leaf vdevs.
             */
            if (zio->io_type == ZIO_TYPE_READ &&
                zio->io_error == ECKSUM &&
                vd->vdev_ops->vdev_op_leaf &&
                vdev_dtl_contains(vd, DTL_MISSING, zio->io_txg, 1))
                return;
        }
    }

    /*
     * For probe failure, we want to avoid posting ereports if we've
     * already removed the device in the meantime.
     */
    if (vd != NULL &&
        strcmp(subclass, FM_EREPORT_ZFS_PROBE_FAILURE) == 0 &&
        (vd->vdev_remove_wanted || vd->vdev_state == VDEV_STATE_REMOVED))
        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.
     */
    fm_payload_set(ereport, FM_EREPORT_PAYLOAD_ZFS_POOL,
        DATA_TYPE_STRING, spa_name(spa), 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 (spa != NULL) {
        fm_payload_set(ereport, FM_EREPORT_PAYLOAD_ZFS_POOL_FAILMODE,
            DATA_TYPE_STRING,
            spa_get_failmode(spa) == ZIO_FAILURE_MODE_WAIT ?
            FM_EREPORT_FAILMODE_WAIT :
            spa_get_failmode(spa) == ZIO_FAILURE_MODE_CONTINUE ?
            FM_EREPORT_FAILMODE_CONTINUE : FM_EREPORT_FAILMODE_PANIC,
            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 != NULL)
            fm_payload_set(ereport,
                FM_EREPORT_PAYLOAD_ZFS_VDEV_PATH,
                DATA_TYPE_STRING, vd->vdev_path, NULL);
        if (vd->vdev_devid != NULL)
            fm_payload_set(ereport,
                FM_EREPORT_PAYLOAD_ZFS_VDEV_DEVID,
                DATA_TYPE_STRING, vd->vdev_devid, NULL);
        if (vd->vdev_fru != NULL)
            fm_payload_set(ereport,
                FM_EREPORT_PAYLOAD_ZFS_VDEV_FRU,
                DATA_TYPE_STRING, vd->vdev_fru, 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,
                    DATA_TYPE_STRING, pvd->vdev_path, NULL);
            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_OBJSET,
                DATA_TYPE_UINT64,
                zio->io_logical->io_bookmark.zb_objset,
                FM_EREPORT_PAYLOAD_ZFS_ZIO_OBJECT,
                DATA_TYPE_UINT64,
                zio->io_logical->io_bookmark.zb_object,
                FM_EREPORT_PAYLOAD_ZFS_ZIO_LEVEL,
                DATA_TYPE_INT64,
                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 (spa->spa_load_state == SPA_LOAD_TRYIMPORT)
        return;

    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.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);
}