cluster/afr: refactor

- Remove client side self-healing completely (opendir, openfd, lookup)
- Re-work readdir-failover to work reliably in case of NFS
- Remove unused/dead lock recovery code
- Consistently use xdata in both calls and callbacks in all FOPs
- Per-inode event generation, used to force inode ctx refresh
- Implement dirty flag support (in place of pending counts)
- Eliminate inode ctx structure, use read subvol bits + event_generation
- Implement inode ctx refreshing based on event generation
- Provide backward compatibility in transactions
- remove unused variables and functions
- make code more consistent in style and pattern
- regularize and clean up inode-write transaction code
- regularize and clean up dir-write transaction code
- regularize and clean up common FOPs
- reorganize transaction framework code
- skip setting xattrs in pending dict if nothing is pending
- re-write self-healing code using syncops
- re-write simpler self-heal-daemon

Change-Id: I1e4080c9796c8a2815c2dab4be3073f389d614a8
BUG: 1021686
Signed-off-by: Anand Avati <avati@redhat.com>
Reviewed-on: http://review.gluster.org/6010
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 0 insertions, 837 deletions

diff --git a/xlators/cluster/afr/src/afr-self-heal-algorithm.c b/xlators/cluster/afr/src/afr-self-heal-algorithm.c
deleted file mode 100644
index 83846f152d2..00000000000
--- a/xlators/cluster/afr/src/afr-self-heal-algorithm.c
+++ /dev/null
@@ -1,837 +0,0 @@
-/*
-  Copyright (c) 2008-2012 Red Hat, Inc. <http://www.redhat.com>
-  This file is part of GlusterFS.
-
-  This file is licensed to you under your choice of the GNU Lesser
-  General Public License, version 3 or any later version (LGPLv3 or
-  later), or the GNU General Public License, version 2 (GPLv2), in all
-  cases as published by the Free Software Foundation.
-*/
-
-
-#include <openssl/md5.h>
-#include "glusterfs.h"
-#include "afr.h"
-#include "xlator.h"
-#include "dict.h"
-#include "xlator.h"
-#include "hashfn.h"
-#include "logging.h"
-#include "stack.h"
-#include "list.h"
-#include "call-stub.h"
-#include "defaults.h"
-#include "common-utils.h"
-#include "compat-errno.h"
-#include "compat.h"
-#include "byte-order.h"
-
-#include "afr-transaction.h"
-#include "afr-self-heal.h"
-#include "afr-self-heal-common.h"
-#include "afr-self-heal-algorithm.h"
-
-/*
-  This file contains the various self-heal algorithms
-*/
-
-static int
-sh_loop_driver (call_frame_t *sh_frame, xlator_t *this,
-                gf_boolean_t is_first_call, call_frame_t *old_loop_frame);
-static int
-sh_loop_return (call_frame_t *sh_frame, xlator_t *this, call_frame_t *loop_frame,
-                int32_t op_ret, int32_t op_errno);
-static int
-sh_destroy_frame (call_frame_t *frame, xlator_t *this)
-{
-        if (!frame)
-                goto out;
-
-        AFR_STACK_DESTROY (frame);
-out:
-        return 0;
-}
-
-static void
-sh_private_cleanup (call_frame_t *frame, xlator_t *this)
-{
-        afr_local_t             *local   = NULL;
-        afr_self_heal_t         *sh      = NULL;
-        afr_sh_algo_private_t   *sh_priv = NULL;
-
-        local = frame->local;
-        sh    = &local->self_heal;
-
-        sh_priv = sh->private;
-        GF_FREE (sh_priv);
-}
-
-static int
-sh_number_of_writes_needed (unsigned char *write_needed, int child_count)
-{
-        int writes = 0;
-        int i      = 0;
-
-        for (i = 0; i < child_count; i++) {
-                if (write_needed[i])
-                        writes++;
-        }
-
-        return writes;
-}
-
-
-static int
-sh_loop_driver_done (call_frame_t *sh_frame, xlator_t *this,
-                     call_frame_t *last_loop_frame)
-{
-        afr_local_t             *local        = NULL;
-        afr_self_heal_t         *sh           = NULL;
-        afr_sh_algo_private_t   *sh_priv      = NULL;
-        int32_t                 total_blocks = 0;
-        int32_t                 diff_blocks  = 0;
-
-        local        = sh_frame->local;
-        sh           = &local->self_heal;
-        sh_priv      = sh->private;
-        if (sh_priv) {
-                total_blocks = sh_priv->total_blocks;
-                diff_blocks  = sh_priv->diff_blocks;
-        }
-
-        sh_private_cleanup (sh_frame, this);
-        if (is_self_heal_failed (sh, AFR_CHECK_SPECIFIC)) {
-                GF_ASSERT (!last_loop_frame);
-                //loop_finish should have happened and the old_loop should be NULL
-                gf_log (this->name, GF_LOG_DEBUG,
-                        "self-heal aborting on %s",
-                        local->loc.path);
-
-                local->self_heal.algo_abort_cbk (sh_frame, this);
-        } else {
-                GF_ASSERT (last_loop_frame);
-                if (diff_blocks == total_blocks) {
-                        gf_log (this->name, GF_LOG_DEBUG, "full self-heal "
-                                "completed on %s",local->loc.path);
-                } else {
-                        gf_log (this->name, GF_LOG_DEBUG,
-                                "diff self-heal on %s: completed. "
-                                "(%d blocks of %d were different (%.2f%%))",
-                                local->loc.path, diff_blocks, total_blocks,
-                                ((diff_blocks * 1.0)/total_blocks) * 100);
-                }
-
-                sh->old_loop_frame = last_loop_frame;
-                local->self_heal.algo_completion_cbk (sh_frame, this);
-        }
-
-        return 0;
-}
-
-int
-sh_loop_finish (call_frame_t *loop_frame, xlator_t *this)
-{
-        afr_local_t             *loop_local = NULL;
-        afr_self_heal_t         *loop_sh = NULL;
-
-        if (!loop_frame)
-                goto out;
-
-        loop_local = loop_frame->local;
-        if (loop_local) {
-                loop_sh = &loop_local->self_heal;
-        }
-
-        if (loop_sh && loop_sh->data_lock_held) {
-                afr_sh_data_unlock (loop_frame, this, this->name,
-                                    sh_destroy_frame);
-        } else {
-                sh_destroy_frame (loop_frame, this);
-        }
-out:
-        return 0;
-}
-
-static int
-sh_loop_lock_success (call_frame_t *loop_frame, xlator_t *this)
-{
-        afr_local_t                 *loop_local = NULL;
-        afr_self_heal_t             *loop_sh    = NULL;
-
-        loop_local = loop_frame->local;
-        loop_sh = &loop_local->self_heal;
-
-        sh_loop_finish (loop_sh->old_loop_frame, this);
-        loop_sh->old_loop_frame = NULL;
-
-        gf_log (this->name, GF_LOG_DEBUG, "Acquired lock for range %"PRIu64
-                " %"PRIu64, loop_sh->offset, loop_sh->block_size);
-        loop_sh->data_lock_held = _gf_true;
-        loop_sh->sh_data_algo_start (loop_frame, this);
-        return 0;
-}
-
-static int
-sh_loop_lock_failure (call_frame_t *loop_frame, xlator_t *this)
-{
-        call_frame_t                *sh_frame = NULL;
-        afr_local_t                 *loop_local = NULL;
-        afr_self_heal_t             *loop_sh    = NULL;
-
-        loop_local = loop_frame->local;
-        loop_sh = &loop_local->self_heal;
-        sh_frame = loop_sh->sh_frame;
-
-        gf_log (this->name, GF_LOG_ERROR, "failed lock for range %"PRIu64
-                " %"PRIu64, loop_sh->offset, loop_sh->block_size);
-        sh_loop_finish (loop_sh->old_loop_frame, this);
-        loop_sh->old_loop_frame = NULL;
-        sh_loop_return (sh_frame, this, loop_frame, -1, ENOTCONN);
-        return 0;
-}
-
-static int
-sh_loop_frame_create (call_frame_t *sh_frame, xlator_t *this,
-                      call_frame_t *old_loop_frame, call_frame_t **loop_frame)
-{
-        call_frame_t                *new_loop_frame = NULL;
-        afr_local_t                 *local          = NULL;
-        afr_self_heal_t             *sh             = NULL;
-        afr_local_t                 *new_loop_local = NULL;
-        afr_self_heal_t             *new_loop_sh    = NULL;
-        afr_private_t               *priv           = NULL;
-
-        GF_ASSERT (sh_frame);
-        GF_ASSERT (loop_frame);
-
-        *loop_frame = NULL;
-        local   = sh_frame->local;
-        sh      = &local->self_heal;
-        priv    = this->private;
-
-        new_loop_frame = copy_frame (sh_frame);
-        if (!new_loop_frame)
-                goto out;
-        //We want the frame to have same lk_owner as sh_frame
-        //so that locks translator allows conflicting locks
-        new_loop_local = afr_self_heal_local_init (local, this);
-        if (!new_loop_local)
-                goto out;
-        new_loop_frame->local = new_loop_local;
-
-        new_loop_sh = &new_loop_local->self_heal;
-        new_loop_sh->sources = memdup (sh->sources,
-                                       priv->child_count * sizeof (*sh->sources));
-        if (!new_loop_sh->sources)
-                goto out;
-        new_loop_sh->write_needed = GF_CALLOC (priv->child_count,
-                                               sizeof (*new_loop_sh->write_needed),
-                                               gf_afr_mt_char);
-        if (!new_loop_sh->write_needed)
-                goto out;
-        new_loop_sh->checksum = GF_CALLOC (priv->child_count, MD5_DIGEST_LENGTH,
-                                           gf_afr_mt_uint8_t);
-        if (!new_loop_sh->checksum)
-                goto out;
-        new_loop_sh->inode      = inode_ref (sh->inode);
-        new_loop_sh->sh_data_algo_start = sh->sh_data_algo_start;
-        new_loop_sh->source = sh->source;
-        new_loop_sh->active_sinks = sh->active_sinks;
-        new_loop_sh->healing_fd = fd_ref (sh->healing_fd);
-        new_loop_sh->file_has_holes = sh->file_has_holes;
-        new_loop_sh->old_loop_frame = old_loop_frame;
-        new_loop_sh->sh_frame = sh_frame;
-        *loop_frame = new_loop_frame;
-        return 0;
-out:
-        sh_destroy_frame (new_loop_frame, this);
-        return -ENOMEM;
-}
-
-static int
-sh_loop_start (call_frame_t *sh_frame, xlator_t *this, off_t offset,
-               call_frame_t *old_loop_frame)
-{
-        call_frame_t                *new_loop_frame = NULL;
-        afr_local_t                 *local          = NULL;
-        afr_self_heal_t             *sh             = NULL;
-        afr_local_t                 *new_loop_local = NULL;
-        afr_self_heal_t             *new_loop_sh    = NULL;
-        int                         ret             = 0;
-
-        GF_ASSERT (sh_frame);
-
-        local   = sh_frame->local;
-        sh      = &local->self_heal;
-
-        ret = sh_loop_frame_create (sh_frame, this, old_loop_frame,
-                                    &new_loop_frame);
-        if (ret)
-                goto out;
-        new_loop_local = new_loop_frame->local;
-        new_loop_sh = &new_loop_local->self_heal;
-        new_loop_sh->offset = offset;
-        new_loop_sh->block_size = sh->block_size;
-        afr_sh_data_lock (new_loop_frame, this, offset, new_loop_sh->block_size,
-                          _gf_true, this->name, sh_loop_lock_success, sh_loop_lock_failure);
-        return 0;
-out:
-        afr_set_self_heal_status (sh, AFR_SELF_HEAL_FAILED);
-        if (old_loop_frame)
-                sh_loop_finish (old_loop_frame, this);
-        sh_loop_return (sh_frame, this, new_loop_frame, -1, ENOMEM);
-        return 0;
-}
-
-static int
-sh_loop_driver (call_frame_t *sh_frame, xlator_t *this,
-                gf_boolean_t is_first_call, call_frame_t *old_loop_frame)
-{
-        afr_local_t *               local          = NULL;
-        afr_self_heal_t *           sh             = NULL;
-        afr_sh_algo_private_t       *sh_priv        = NULL;
-        gf_boolean_t                is_driver_done = _gf_false;
-        blksize_t                   block_size     = 0;
-        int                         loop           = 0;
-        off_t                       offset         = 0;
-        afr_private_t               *priv          = NULL;
-
-        priv    = this->private;
-        local   = sh_frame->local;
-        sh      = &local->self_heal;
-        sh_priv = sh->private;
-
-        LOCK (&sh_priv->lock);
-        {
-                if (!is_first_call)
-                        sh_priv->loops_running--;
-                offset = sh_priv->offset;
-                block_size = sh->block_size;
-                while ((!sh->eof_reached) &&
-                       (!is_self_heal_failed (sh, AFR_CHECK_SPECIFIC)) &&
-                     (sh_priv->loops_running < priv->data_self_heal_window_size)
-                       && (sh_priv->offset < sh->file_size)) {
-
-                        loop++;
-                        sh_priv->offset += block_size;
-                        sh_priv->loops_running++;
-
-                        if (!is_first_call)
-                                break;
-                }
-                if (0 == sh_priv->loops_running) {
-                        is_driver_done = _gf_true;
-                }
-        }
-        UNLOCK (&sh_priv->lock);
-
-        if (0 == loop) {
-                //loop finish does unlock, but the erasing of the pending
-                //xattrs needs to happen before that so do not finish the loop
-                if (is_driver_done &&
-                    !is_self_heal_failed (sh, AFR_CHECK_SPECIFIC))
-                        goto driver_done;
-                if (old_loop_frame) {
-                        sh_loop_finish (old_loop_frame, this);
-                        old_loop_frame = NULL;
-                }
-        }
-
-        //If we have more loops to form we should finish previous loop after
-        //the next loop lock
-        while (loop--) {
-                if (is_self_heal_failed (sh, AFR_CHECK_SPECIFIC)) {
-                        // op failed in other loop, stop spawning more loops
-                        if (old_loop_frame) {
-                                sh_loop_finish (old_loop_frame, this);
-                                old_loop_frame = NULL;
-                        }
-                        sh_loop_driver (sh_frame, this, _gf_false, NULL);
-                } else {
-                        gf_log (this->name, GF_LOG_TRACE, "spawning a loop "
-                                "for offset %"PRId64, offset);
-
-                        sh_loop_start (sh_frame, this, offset, old_loop_frame);
-                        old_loop_frame = NULL;
-                        offset += block_size;
-                }
-        }
-
-driver_done:
-        if (is_driver_done) {
-                sh_loop_driver_done (sh_frame, this, old_loop_frame);
-        }
-        return 0;
-}
-
-static int
-sh_loop_return (call_frame_t *sh_frame, xlator_t *this, call_frame_t *loop_frame,
-                int32_t op_ret, int32_t op_errno)
-{
-        afr_local_t *               loop_local = NULL;
-        afr_self_heal_t *           loop_sh    = NULL;
-        afr_local_t *               sh_local = NULL;
-        afr_self_heal_t            *sh       = NULL;
-
-        sh_local = sh_frame->local;
-        sh       = &sh_local->self_heal;
-
-        if (loop_frame) {
-                loop_local = loop_frame->local;
-                if (loop_local)
-                        loop_sh    = &loop_local->self_heal;
-                if (loop_sh)
-                        gf_log (this->name, GF_LOG_TRACE, "loop for offset "
-                                "%"PRId64" returned", loop_sh->offset);
-        }
-
-        if (op_ret == -1) {
-                afr_set_self_heal_status (sh, AFR_SELF_HEAL_FAILED);
-                afr_sh_set_error (sh, op_errno);
-                if (loop_frame) {
-                        sh_loop_finish (loop_frame, this);
-                        loop_frame = NULL;
-                }
-        }
-
-        sh_loop_driver (sh_frame, this, _gf_false, loop_frame);
-
-        return 0;
-}
-
-static int
-sh_loop_write_cbk (call_frame_t *loop_frame, void *cookie, xlator_t *this,
-                   int32_t op_ret, int32_t op_errno, struct iatt *buf,
-                   struct iatt *postbuf, dict_t *xdata)
-{
-        afr_private_t *             priv        = NULL;
-        afr_local_t *               loop_local    = NULL;
-        afr_self_heal_t *           loop_sh       = NULL;
-        call_frame_t               *sh_frame    = NULL;
-        afr_local_t *               sh_local    = NULL;
-        afr_self_heal_t            *sh          = NULL;
-        int                         call_count  = 0;
-        int                         child_index = 0;
-
-        priv     = this->private;
-        loop_local = loop_frame->local;
-        loop_sh    = &loop_local->self_heal;
-
-        sh_frame = loop_sh->sh_frame;
-        sh_local = sh_frame->local;
-        sh       = &sh_local->self_heal;
-
-        child_index =  (long) cookie;
-
-        gf_log (this->name, GF_LOG_TRACE,
-                "wrote %d bytes of data from %s to child %d, offset %"PRId64"",
-                op_ret, sh_local->loc.path, child_index, loop_sh->offset);
-
-        if (op_ret == -1) {
-                gf_log (this->name, GF_LOG_ERROR,
-                        "write to %s failed on subvolume %s (%s)",
-                        sh_local->loc.path,
-                        priv->children[child_index]->name,
-                        strerror (op_errno));
-
-                afr_set_self_heal_status (sh, AFR_SELF_HEAL_FAILED);
-                afr_sh_set_error (loop_sh, op_errno);
-        } else if (op_ret < loop_local->cont.writev.vector->iov_len) {
-                gf_log (this->name, GF_LOG_ERROR,
-                        "incomplete write to %s on subvolume %s "
-                        "(expected %lu, returned %d)", sh_local->loc.path,
-                        priv->children[child_index]->name,
-                        loop_local->cont.writev.vector->iov_len, op_ret);
-                afr_set_self_heal_status (sh, AFR_SELF_HEAL_FAILED);
-        }
-
-        call_count = afr_frame_return (loop_frame);
-
-        if (call_count == 0) {
-		iobref_unref(loop_local->cont.writev.iobref);
-
-                sh_loop_return (sh_frame, this, loop_frame,
-                                loop_sh->op_ret, loop_sh->op_errno);
-        }
-
-        return 0;
-}
-
-static void
-sh_prune_writes_needed (call_frame_t *sh_frame, call_frame_t *loop_frame,
-                        afr_private_t *priv)
-{
-        afr_local_t     *sh_local     = NULL;
-        afr_self_heal_t *sh           = NULL;
-        afr_local_t     *loop_local   = NULL;
-        afr_self_heal_t *loop_sh      = NULL;
-        int             i             = 0;
-
-        sh_local   = sh_frame->local;
-        sh         = &sh_local->self_heal;
-
-        if (!strcmp (sh->algo->name, "diff"))
-                return;
-
-        loop_local = loop_frame->local;
-        loop_sh    = &loop_local->self_heal;
-
-        /* full self-heal guarantees there exists atleast 1 file with size 0
-         * That means for other files we can preserve holes that come after
-         * its size before 'trim'
-         */
-        for (i = 0; i < priv->child_count; i++) {
-                if (loop_sh->write_needed[i] &&
-                    ((loop_sh->offset + 1) > sh->buf[i].ia_size))
-                        loop_sh->write_needed[i] = 0;
-        }
-}
-
-static int
-sh_loop_read_cbk (call_frame_t *loop_frame, void *cookie,
-                  xlator_t *this, int32_t op_ret, int32_t op_errno,
-                  struct iovec *vector, int32_t count, struct iatt *buf,
-                  struct iobref *iobref, dict_t *xdata)
-{
-        afr_private_t *               priv       = NULL;
-        afr_local_t *                 loop_local   = NULL;
-        afr_self_heal_t *             loop_sh      = NULL;
-        call_frame_t                 *sh_frame   = NULL;
-        int                           i          = 0;
-        int                           call_count = 0;
-        afr_local_t *                 sh_local   = NULL;
-        afr_self_heal_t *             sh      = NULL;
-
-        priv       = this->private;
-        loop_local = loop_frame->local;
-        loop_sh    = &loop_local->self_heal;
-
-        sh_frame = loop_sh->sh_frame;
-        sh_local = sh_frame->local;
-        sh       = &sh_local->self_heal;
-
-        gf_log (this->name, GF_LOG_TRACE,
-                "read %d bytes of data from %s, offset %"PRId64"",
-                op_ret, loop_local->loc.path, loop_sh->offset);
-
-        if (op_ret <= 0) {
-                if (op_ret < 0) {
-                        afr_set_self_heal_status (sh, AFR_SELF_HEAL_FAILED);
-                        gf_log (this->name, GF_LOG_ERROR, "read failed on %d "
-                                "for %s reason :%s", sh->source,
-                                sh_local->loc.path, strerror (errno));
-                } else {
-                        sh->eof_reached = _gf_true;
-                        gf_log (this->name, GF_LOG_DEBUG, "Eof reached for %s",
-                                sh_local->loc.path);
-                }
-                sh_loop_return (sh_frame, this, loop_frame, op_ret, op_errno);
-                goto out;
-        }
-
-        if (loop_sh->file_has_holes && iov_0filled (vector, count) == 0)
-                sh_prune_writes_needed (sh_frame, loop_frame, priv);
-
-        call_count = sh_number_of_writes_needed (loop_sh->write_needed,
-                                                 priv->child_count);
-        if (call_count == 0) {
-                sh_loop_return (sh_frame, this, loop_frame, 0, 0);
-                goto out;
-        }
-
-        loop_local->call_count = call_count;
-
-	/*
-	 * We only really need the request size at the moment, but the buffer
-	 * is required if we want to issue a retry in the event of a short write.
-	 * Therefore, we duplicate the vector and ref the iobref here...
-	 */
-	loop_local->cont.writev.vector = iov_dup(vector, count);
-	loop_local->cont.writev.iobref = iobref_ref(iobref);
-
-        for (i = 0; i < priv->child_count; i++) {
-                if (!loop_sh->write_needed[i])
-                        continue;
-                STACK_WIND_COOKIE (loop_frame, sh_loop_write_cbk,
-                                   (void *) (long) i,
-                                   priv->children[i],
-                                   priv->children[i]->fops->writev,
-                                   loop_sh->healing_fd, vector, count,
-                                   loop_sh->offset, 0, iobref, NULL);
-
-                if (!--call_count)
-                        break;
-        }
-
-out:
-        return 0;
-}
-
-
-static int
-sh_loop_read (call_frame_t *loop_frame, xlator_t *this)
-{
-        afr_private_t           *priv       = NULL;
-        afr_local_t             *loop_local   = NULL;
-        afr_self_heal_t         *loop_sh      = NULL;
-
-        priv     = this->private;
-        loop_local = loop_frame->local;
-        loop_sh    = &loop_local->self_heal;
-
-        STACK_WIND_COOKIE (loop_frame, sh_loop_read_cbk,
-                           (void *) (long) loop_sh->source,
-                           priv->children[loop_sh->source],
-                           priv->children[loop_sh->source]->fops->readv,
-                           loop_sh->healing_fd, loop_sh->block_size,
-                           loop_sh->offset, 0, NULL);
-
-        return 0;
-}
-
-
-static int
-sh_diff_checksum_cbk (call_frame_t *loop_frame, void *cookie, xlator_t *this,
-                      int32_t op_ret, int32_t op_errno,
-                      uint32_t weak_checksum, uint8_t *strong_checksum,
-                      dict_t *xdata)
-{
-        afr_private_t                 *priv         = NULL;
-        afr_local_t                   *loop_local   = NULL;
-        afr_self_heal_t               *loop_sh      = NULL;
-        call_frame_t                  *sh_frame     = NULL;
-        afr_local_t                   *sh_local     = NULL;
-        afr_self_heal_t               *sh           = NULL;
-        afr_sh_algo_private_t         *sh_priv      = NULL;
-        int                           child_index  = 0;
-        int                           call_count   = 0;
-        int                           i            = 0;
-        int                           write_needed = 0;
-
-        priv  = this->private;
-
-        loop_local = loop_frame->local;
-        loop_sh    = &loop_local->self_heal;
-
-        sh_frame = loop_sh->sh_frame;
-        sh_local = sh_frame->local;
-        sh       = &sh_local->self_heal;
-
-        sh_priv = sh->private;
-
-        child_index = (long) cookie;
-
-        if (op_ret < 0) {
-                gf_log (this->name, GF_LOG_ERROR,
-                        "checksum on %s failed on subvolume %s (%s)",
-                        sh_local->loc.path, priv->children[child_index]->name,
-                        strerror (op_errno));
-                afr_set_self_heal_status (sh, AFR_SELF_HEAL_FAILED);
-        } else {
-                memcpy (loop_sh->checksum + child_index * MD5_DIGEST_LENGTH,
-                        strong_checksum, MD5_DIGEST_LENGTH);
-        }
-
-        call_count = afr_frame_return (loop_frame);
-
-        if (call_count == 0) {
-                for (i = 0; i < priv->child_count; i++) {
-                        if (sh->sources[i] || !sh_local->child_up[i])
-                                continue;
-
-                        if (memcmp (loop_sh->checksum + (i * MD5_DIGEST_LENGTH),
-                                    loop_sh->checksum + (sh->source * MD5_DIGEST_LENGTH),
-                                    MD5_DIGEST_LENGTH)) {
-                                /*
-                                  Checksums differ, so this block
-                                  must be written to this sink
-                                */
-
-                                gf_log (this->name, GF_LOG_DEBUG,
-                                        "checksum on subvolume %s at offset %"
-                                        PRId64" differs from that on source",
-                                        priv->children[i]->name, loop_sh->offset);
-
-                                write_needed = loop_sh->write_needed[i] = 1;
-                        }
-                }
-
-                LOCK (&sh_priv->lock);
-                {
-                        sh_priv->total_blocks++;
-                        if (write_needed)
-                                sh_priv->diff_blocks++;
-                }
-                UNLOCK (&sh_priv->lock);
-
-                if (write_needed &&
-                    !is_self_heal_failed (sh, AFR_CHECK_SPECIFIC)) {
-                        sh_loop_read (loop_frame, this);
-                } else {
-                        sh_loop_return (sh_frame, this, loop_frame,
-                                        op_ret, op_errno);
-                }
-        }
-
-        return 0;
-}
-
-static int
-sh_diff_checksum (call_frame_t *loop_frame, xlator_t *this)
-{
-        afr_private_t           *priv         = NULL;
-        afr_local_t             *loop_local   = NULL;
-        afr_self_heal_t         *loop_sh      = NULL;
-        int                     call_count    = 0;
-        int                     i             = 0;
-
-        priv         = this->private;
-        loop_local   = loop_frame->local;
-        loop_sh      = &loop_local->self_heal;
-
-        call_count = loop_sh->active_sinks + 1;  /* sinks and source */
-
-        loop_local->call_count = call_count;
-
-        STACK_WIND_COOKIE (loop_frame, sh_diff_checksum_cbk,
-                           (void *) (long) loop_sh->source,
-                           priv->children[loop_sh->source],
-                           priv->children[loop_sh->source]->fops->rchecksum,
-                           loop_sh->healing_fd,
-                           loop_sh->offset, loop_sh->block_size, NULL);
-
-        for (i = 0; i < priv->child_count; i++) {
-                if (loop_sh->sources[i] || !loop_local->child_up[i])
-                        continue;
-
-                STACK_WIND_COOKIE (loop_frame, sh_diff_checksum_cbk,
-                                   (void *) (long) i,
-                                   priv->children[i],
-                                   priv->children[i]->fops->rchecksum,
-                                   loop_sh->healing_fd,
-                                   loop_sh->offset, loop_sh->block_size, NULL);
-
-                if (!--call_count)
-                        break;
-        }
-
-        return 0;
-}
-
-static int
-sh_full_read_write_to_sinks (call_frame_t *loop_frame, xlator_t *this)
-{
-        afr_private_t           *priv         = NULL;
-        afr_local_t             *loop_local   = NULL;
-        afr_self_heal_t         *loop_sh      = NULL;
-        int                     i             = 0;
-
-        priv         = this->private;
-        loop_local   = loop_frame->local;
-        loop_sh      = &loop_local->self_heal;
-
-        for (i = 0; i < priv->child_count; i++) {
-                if (loop_sh->sources[i] || !loop_local->child_up[i])
-                        continue;
-                loop_sh->write_needed[i] = 1;
-        }
-        sh_loop_read (loop_frame, this);
-        return 0;
-}
-
-afr_sh_algo_private_t*
-afr_sh_priv_init ()
-{
-        afr_sh_algo_private_t   *sh_priv = NULL;
-
-        sh_priv = GF_CALLOC (1, sizeof (*sh_priv),
-                             gf_afr_mt_afr_private_t);
-        if (!sh_priv)
-                goto out;
-
-        LOCK_INIT (&sh_priv->lock);
-out:
-        return sh_priv;
-}
-
-int
-afr_sh_transfer_lock (call_frame_t *dst, call_frame_t *src, char *dom,
-                      unsigned int child_count)
-{
-        afr_local_t             *dst_local   = NULL;
-        afr_self_heal_t         *dst_sh      = NULL;
-        afr_local_t             *src_local   = NULL;
-        afr_self_heal_t         *src_sh      = NULL;
-        int                     ret          = -1;
-
-        dst_local = dst->local;
-        dst_sh = &dst_local->self_heal;
-        src_local = src->local;
-        src_sh = &src_local->self_heal;
-        GF_ASSERT (src_sh->data_lock_held);
-        GF_ASSERT (!dst_sh->data_lock_held);
-        ret = afr_lk_transfer_datalock (dst, src, dom, child_count);
-        if (ret)
-                return ret;
-        src_sh->data_lock_held = _gf_false;
-        dst_sh->data_lock_held = _gf_true;
-        return 0;
-}
-
-int
-afr_sh_start_loops (call_frame_t *sh_frame, xlator_t *this,
-                    afr_sh_algo_fn sh_data_algo_start)
-{
-        call_frame_t            *first_loop_frame = NULL;
-        afr_local_t             *local   = NULL;
-        afr_self_heal_t         *sh      = NULL;
-        int                     ret      = 0;
-        afr_private_t           *priv    = NULL;
-
-        local = sh_frame->local;
-        sh    = &local->self_heal;
-        priv  = this->private;
-
-        sh->sh_data_algo_start = sh_data_algo_start;
-        local->call_count = 0;
-        ret = sh_loop_frame_create (sh_frame, this, NULL, &first_loop_frame);
-        if (ret)
-                goto out;
-        ret = afr_sh_transfer_lock (first_loop_frame, sh_frame, this->name,
-                                    priv->child_count);
-        if (ret)
-                goto out;
-        sh->private = afr_sh_priv_init ();
-        if (!sh->private) {
-                ret = -1;
-                goto out;
-        }
-        sh_loop_driver (sh_frame, this, _gf_true, first_loop_frame);
-        ret = 0;
-out:
-        if (ret) {
-                afr_set_self_heal_status (sh, AFR_SELF_HEAL_FAILED);
-                sh_loop_driver_done (sh_frame, this, NULL);
-        }
-        return 0;
-}
-
-int
-afr_sh_algo_diff (call_frame_t *sh_frame, xlator_t *this)
-{
-        afr_sh_start_loops (sh_frame, this, sh_diff_checksum);
-        return 0;
-}
-
-int
-afr_sh_algo_full (call_frame_t *sh_frame, xlator_t *this)
-{
-        afr_sh_start_loops (sh_frame, this, sh_full_read_write_to_sinks);
-        return 0;
-}
-
-struct afr_sh_algorithm afr_self_heal_algorithms[] = {
-        {.name = "full",  .fn = afr_sh_algo_full},
-        {.name = "diff",  .fn = afr_sh_algo_diff},
-        {0, 0},
-};