cluster/afr: Handle self-heal of files with holes

Change-Id: I6c04fe3022f234455d52620f42b9add80fc6abe4
BUG: 765424
Signed-off-by: Pranith Kumar K <pranithk@gluster.com>
Reviewed-on: http://review.gluster.com/3065
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>

4 files changed, 45 insertions, 15 deletions

diff --git a/xlators/cluster/afr/src/afr-self-heal-algorithm.c b/xlators/cluster/afr/src/afr-self-heal-algorithm.c
index 6bd0adcd851..99a2108361c 100644
--- a/xlators/cluster/afr/src/afr-self-heal-algorithm.c
+++ b/xlators/cluster/afr/src/afr-self-heal-algorithm.c
@@ -456,6 +456,35 @@ sh_loop_write_cbk (call_frame_t *loop_frame, void *cookie, xlator_t *this,
         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,
@@ -499,16 +528,15 @@ sh_loop_read_cbk (call_frame_t *loop_frame, void *cookie,
                 goto out;
         }
 
-        if (loop_sh->file_has_holes && iov_0filled (vector, count) == 0) {
-                        gf_log (this->name, GF_LOG_DEBUG, "0 filled block");
-                        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);
-        GF_ASSERT (call_count > 0);
+        if (call_count == 0) {
+                sh_loop_return (sh_frame, this, loop_frame, 0, 0);
+                goto out;
+        }
         loop_local->call_count = call_count;
 
         for (i = 0; i < priv->child_count; i++) {
diff --git a/xlators/cluster/afr/src/afr-self-heal-algorithm.h b/xlators/cluster/afr/src/afr-self-heal-algorithm.h
index 04d8e8a6ce7..27d3d171bb9 100644
--- a/xlators/cluster/afr/src/afr-self-heal-algorithm.h
+++ b/xlators/cluster/afr/src/afr-self-heal-algorithm.h
@@ -20,7 +20,6 @@
 #ifndef __AFR_SELF_HEAL_ALGORITHM_H__
 #define __AFR_SELF_HEAL_ALGORITHM_H__
 
-
 typedef int (*afr_sh_algo_fn) (call_frame_t *frame,
                                xlator_t *this);
 
diff --git a/xlators/cluster/afr/src/afr-self-heal-data.c b/xlators/cluster/afr/src/afr-self-heal-data.c
index bf37729fe82..d362d5add6f 100644
--- a/xlators/cluster/afr/src/afr-self-heal-data.c
+++ b/xlators/cluster/afr/src/afr-self-heal-data.c
@@ -492,12 +492,16 @@ sh_algo_from_name (xlator_t *this, char *name)
 
 
 static int
-sh_zero_byte_files_exist (afr_self_heal_t *sh, int child_count)
+sh_zero_byte_files_exist (afr_local_t *local, int child_count)
 {
-        int i;
-        int ret = 0;
+        int             i = 0;
+        int             ret = 0;
+        afr_self_heal_t *sh = NULL;
 
+        sh = &local->self_heal;
         for (i = 0; i < child_count; i++) {
+                if (!local->child_up[i] || sh->child_errno[i])
+                        continue;
                 if (sh->buf[i].ia_size == 0) {
                         ret = 1;
                         break;
@@ -524,8 +528,7 @@ afr_sh_data_pick_algo (call_frame_t *frame, xlator_t *this)
         if (algo == NULL) {
                 /* option not set, so fall back on heuristics */
 
-                if ((local->enoent_count != 0)
-                    || sh_zero_byte_files_exist (sh, priv->child_count)
+                if (sh_zero_byte_files_exist (local, priv->child_count)
                     || (sh->file_size <= (priv->data_self_heal_window_size *
                                           this->ctx->page_size))) {
 
@@ -568,6 +571,7 @@ afr_sh_data_sync_prepare (call_frame_t *frame, xlator_t *this)
 
         sh_algo = afr_sh_data_pick_algo (frame, this);
 
+        sh->algo = sh_algo;
         sh_algo->fn (frame, this);
 
         return 0;
@@ -944,8 +948,6 @@ afr_sh_data_fstat (call_frame_t *frame, xlator_t *this)
         local->call_count = call_count;
 
         afr_reset_children (sh->success_children, priv->child_count);
-        memset (sh->child_errno, 0,
-                sizeof (*sh->child_errno) * priv->child_count);
         sh->success_count = 0;
         for (i = 0; i < priv->child_count; i++) {
                 child = fstat_children[i];
diff --git a/xlators/cluster/afr/src/afr.h b/xlators/cluster/afr/src/afr.h
index 918e44d7d92..815f4667c0b 100644
--- a/xlators/cluster/afr/src/afr.h
+++ b/xlators/cluster/afr/src/afr.h
@@ -261,6 +261,7 @@ typedef struct {
 
         afr_sh_algo_private_t *private;
 
+        struct afr_sh_algorithm  *algo;
         afr_lock_cbk_t data_lock_success_handler;
         afr_lock_cbk_t data_lock_failure_handler;
         int (*completion_cbk) (call_frame_t *frame, xlator_t *this);