features/shard: Implement discard fop

Change-Id: Ia5bd8d36b21a586df6556fbec3474892d5871229
BUG: 1261841
Signed-off-by: Krutika Dhananjay <kdhananj@redhat.com>
Reviewed-on: http://review.gluster.org/13657
Smoke: Gluster Build System <jenkins@build.gluster.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
Tested-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
CentOS-regression: Gluster Build System <jenkins@build.gluster.com>

9 files changed, 167 insertions, 30 deletions

diff --git a/tests/bugs/shard/bug-1260637.t b/tests/bugs/shard/bug-1260637.t
index f5bf083b5dc..21008ee19dd 100644
--- a/tests/bugs/shard/bug-1260637.t
+++ b/tests/bugs/shard/bug-1260637.t
@@ -1,6 +1,7 @@
 #!/bin/bash
 
 . $(dirname $0)/../../include.rc
+. $(dirname $0)/../../volume.rc
 
 cleanup
 
@@ -34,7 +35,7 @@ TEST ! setfattr -x trusted.glusterfs.shard.file-size $M0/foo
 # Verify that shard xattrs are not listed when listxattr is triggered.
 TEST ! "getfattr -d -m . $M0/foo | grep shard"
 
-TEST umount $M0
+EXPECT_WITHIN $UMOUNT_TIMEOUT "Y" force_umount $M0
 TEST $CLI volume stop $V0
 TEST $CLI volume delete $V0
 
diff --git a/tests/bugs/shard/bug-shard-discard.c b/tests/bugs/shard/bug-shard-discard.c
new file mode 100644
index 00000000000..d51b07f9314
--- /dev/null
+++ b/tests/bugs/shard/bug-shard-discard.c
@@ -0,0 +1,66 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "glfs.h"
+#include "glfs-handles.h"
+
+int
+main (int argc, char *argv[])
+{
+        int        ret = 0;
+        off_t      off = 0;
+        size_t     len = 0;
+        glfs_t    *fs  = NULL;
+        glfs_fd_t *fd  = NULL;
+
+        if (argc != 7) {
+                fprintf (stderr, "Syntax: %s <host> <volname> <file-path> <off> <len> <log-file>\n", argv[0]);
+                return 1;
+        }
+
+        fs = glfs_new (argv[2]);
+        if (!fs) {
+                fprintf (stderr, "glfs_new: returned NULL\n");
+                return 1;
+        }
+
+        ret = glfs_set_volfile_server (fs, "tcp", argv[1], 24007);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_set_volfile_server: retuned %d\n", ret);
+                goto out;
+        }
+
+        ret = glfs_set_logging (fs, argv[6], 7);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_set_logging: returned %d\n", ret);
+                goto out;
+        }
+
+        ret = glfs_init (fs);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_init: returned %d\n", ret);
+                goto out;
+        }
+
+        fd = glfs_open (fs, argv[3], O_RDWR);
+        if (fd == NULL) {
+                fprintf (stderr, "glfs_open: returned NULL\n");
+                goto out;
+        }
+
+        off = atoi (argv[4]);
+        len = atoi (argv[5]);
+
+        ret = glfs_discard (fd, off, len);
+        if (ret <= 0) {
+                fprintf (stderr, "glfs_discard: returned %d\n", ret);
+                goto out;
+        }
+
+        ret = 0;
+
+out:
+        if (fd)
+                glfs_close (fd);
+        glfs_fini (fs);
+        return ret;
+}
diff --git a/tests/bugs/shard/bug-shard-discard.t b/tests/bugs/shard/bug-shard-discard.t
new file mode 100644
index 00000000000..4c4e9417b5b
--- /dev/null
+++ b/tests/bugs/shard/bug-shard-discard.t
@@ -0,0 +1,61 @@
+#!/bin/bash
+
+. $(dirname $0)/../../include.rc
+. $(dirname $0)/../../volume.rc
+
+cleanup
+
+TEST glusterd
+TEST pidof glusterd
+TEST $CLI volume create $V0 replica 2 $H0:$B0/${V0}{0..3}
+TEST $CLI volume set $V0 features.shard on
+TEST $CLI volume start $V0
+
+TEST $GFS --volfile-id=$V0 --volfile-server=$H0 $M0
+
+# Create a file.
+TEST touch $M0/foo
+TEST dd if=/dev/urandom of=$M0/foo bs=1M count=10
+
+# This should ensure /.shard is created on the bricks.
+TEST stat $B0/${V0}0/.shard
+TEST stat $B0/${V0}1/.shard
+TEST stat $B0/${V0}2/.shard
+TEST stat $B0/${V0}3/.shard
+
+#Note the size of the file, it should be 10M
+EXPECT '10485760' stat -c %s $M0/foo
+
+gfid_foo=$(get_gfid_string $M0/foo)
+
+TEST gcc -Wall -O2 -I api/src -o $(dirname $0)/bug-shard-discard $(dirname $0)/bug-shard-discard.c -lgfapi
+#Call discard on the file at off=7M and len=3M
+TEST $(dirname $0)/bug-shard-discard $H0 $V0 /foo 7340032 3145728 `gluster --print-logdir`/glfs-$V0.log
+
+#Ensure that discard doesn't change the original size of the file.
+EXPECT '10485760' stat -c %s $M0/foo
+
+# Ensure that the last shard is all zero'd out
+EXPECT "1" file_all_zeroes `find $B0 -name $gfid_foo.2`
+EXPECT_NOT "1" file_all_zeroes `find $B0 -name $gfid_foo.1`
+
+# Now unlink the file. And ensure that all shards associated with the file are cleaned up
+TEST unlink $M0/foo
+TEST ! stat $B0/${V0}0/.shard/$gfid_foo.1
+TEST ! stat $B0/${V0}1/.shard/$gfid_foo.1
+TEST ! stat $B0/${V0}2/.shard/$gfid_foo.1
+TEST ! stat $B0/${V0}3/.shard/$gfid_foo.1
+TEST ! stat $B0/${V0}0/.shard/$gfid_foo.2
+TEST ! stat $B0/${V0}1/.shard/$gfid_foo.2
+TEST ! stat $B0/${V0}2/.shard/$gfid_foo.2
+TEST ! stat $B0/${V0}3/.shard/$gfid_foo.2
+TEST ! stat $M0/foo
+
+#clean up everything
+EXPECT_WITHIN $UMOUNT_TIMEOUT "Y" force_umount $M0
+TEST $CLI volume stop $V0
+TEST $CLI volume delete $V0
+
+TEST rm -f $(dirname $0)/bug-shard-discard
+
+cleanup
diff --git a/tests/bugs/shard/bug-shard-zerofill.c b/tests/bugs/shard/bug-shard-zerofill.c
index 728e492c7ed..f88c2e2fd02 100644
--- a/tests/bugs/shard/bug-shard-zerofill.c
+++ b/tests/bugs/shard/bug-shard-zerofill.c
@@ -9,8 +9,8 @@ main (int argc, char *argv[])
         glfs_fd_t *fd = NULL;
         int        ret = 1;
 
-        if (argc != 4) {
-                fprintf (stderr, "Syntax: %s <host> <volname> <file-path> \n", argv[0]);
+        if (argc != 5) {
+                fprintf (stderr, "Syntax: %s <host> <volname> <file-path> <log-file>\n", argv[0]);
                 return 1;
         }
 
@@ -25,7 +25,7 @@ main (int argc, char *argv[])
                 fprintf (stderr, "glfs_set_volfile_server: retuned %d\n", ret);
                 goto out;
         }
-        ret = glfs_set_logging (fs, "/var/log/glusterfs/glfs-dis.log", 7);
+        ret = glfs_set_logging (fs, argv[4], 7);
         if (ret != 0) {
                 fprintf (stderr, "glfs_set_logging: returned %d\n", ret);
                 goto out;
diff --git a/tests/bugs/shard/bug-shard-zerofill.t b/tests/bugs/shard/bug-shard-zerofill.t
index c3211493fe1..ad508c83236 100644
--- a/tests/bugs/shard/bug-shard-zerofill.t
+++ b/tests/bugs/shard/bug-shard-zerofill.t
@@ -3,10 +3,6 @@
 . $(dirname $0)/../../include.rc
 . $(dirname $0)/../../volume.rc
 
-function file_all_zeroes {
-        < $1 tr -d '\0' | read -n 1 || echo 1
-}
-
 cleanup
 
 TEST glusterd
@@ -23,7 +19,7 @@ TEST touch $M0/foo
 gfid_foo=$(get_gfid_string $M0/foo)
 
 TEST gcc -Wall -O2 -I api/src -o $(dirname $0)/bug-shard-zerofill $(dirname $0)/bug-shard-zerofill.c -lgfapi
-TEST $(dirname $0)/bug-shard-zerofill $H0 $V0 /foo
+TEST $(dirname $0)/bug-shard-zerofill $H0 $V0 /foo `gluster --print-logdir`/glfs-$V0.log
 
 # This should ensure /.shard is created on the bricks.
 TEST stat $B0/${V0}0/.shard
@@ -40,7 +36,7 @@ TEST `echo "abc" >> $M0/foo`
 
 EXPECT_NOT "1" file_all_zeroes $M0/foo
 
-TEST umount $M0
+EXPECT_WITHIN $UMOUNT_TIMEOUT "Y" force_umount $M0
 TEST $CLI volume stop $V0
 TEST $CLI volume delete $V0
 
diff --git a/tests/bugs/shard/shard-fallocate.c b/tests/bugs/shard/shard-fallocate.c
index fded6236552..5365c74ef86 100644
--- a/tests/bugs/shard/shard-fallocate.c
+++ b/tests/bugs/shard/shard-fallocate.c
@@ -45,12 +45,11 @@ main (int argc, char *argv[])
         int        opcode = -1;
         off_t      offset = 0;
         size_t     len = 0;
-        char       logpath[PATH_MAX] = {0,};
         glfs_t    *fs = NULL;
         glfs_fd_t *fd = NULL;
 
-        if (argc != 7) {
-                fprintf (stderr, "Syntax: %s <host> <volname> <opcode> <offset> <len> <file-path>\n", argv[0]);
+        if (argc != 8) {
+                fprintf (stderr, "Syntax: %s <host> <volname> <opcode> <offset> <len> <file-path> <log-file>\n", argv[0]);
                 return 1;
         }
 
@@ -60,16 +59,13 @@ main (int argc, char *argv[])
                 return 1;
         }
 
-        snprintf (logpath, sizeof (logpath), "/var/log/glusterfs/glfs-%s.log",
-                  argv[2]);
-
         ret = glfs_set_volfile_server (fs, "tcp", argv[1], 24007);
         if (ret != 0) {
                 fprintf (stderr, "glfs_set_volfile_server: retuned %d\n", ret);
                 goto out;
         }
 
-        ret = glfs_set_logging (fs, logpath, 7);
+        ret = glfs_set_logging (fs, argv[7], 7);
         if (ret != 0) {
                 fprintf (stderr, "glfs_set_logging: returned %d\n", ret);
                 goto out;
diff --git a/tests/bugs/shard/zero-flag.t b/tests/bugs/shard/zero-flag.t
index dc88ae1c1ca..fabf83040f0 100644
--- a/tests/bugs/shard/zero-flag.t
+++ b/tests/bugs/shard/zero-flag.t
@@ -4,10 +4,6 @@
 . $(dirname $0)/../../volume.rc
 . $(dirname $0)/../../fallocate.rc
 
-function file_all_zeroes {
-        < $1 tr -d '\0' | read -n 1 || echo 1
-}
-
 cleanup
 
 require_fallocate -l 1m $M0/file
@@ -31,7 +27,7 @@ TEST touch $M0/file1
 
 gfid_file1=$(get_gfid_string $M0/file1)
 
-TEST $(dirname $0)/zero-flag $H0 $V0 "0" "0" "6291456" /file1
+TEST $(dirname $0)/zero-flag $H0 $V0 "0" "0" "6291456" /file1 `gluster --print-logdir`/glfs-$V0.log
 
 EXPECT '6291456' stat -c %s $M0/file1
 
@@ -51,7 +47,7 @@ TEST truncate -s 6M $M0/file2
 TEST dd if=$M0/tmp of=$M0/file2 bs=1 seek=3145728 count=26 conv=notrunc
 md5sum_file2=$(md5sum $M0/file2 | awk '{print $1}')
 
-TEST $(dirname $0)/zero-flag $H0 $V0 "0" "3145728" "26" /file2
+TEST $(dirname $0)/zero-flag $H0 $V0 "0" "3145728" "26" /file2 `gluster --print-logdir`/glfs-$V0.log
 
 EXPECT '6291456' stat -c %s $M0/file2
 EXPECT "$md5sum_file2" echo `md5sum $M0/file2 | awk '{print $1}'`
@@ -69,10 +65,10 @@ TEST   stat $B0/$V0*/.shard/$gfid_file3.2
 md5sum_file3=$(md5sum $M0/file3 | awk '{print $1}')
 EXPECT "1048602" echo `find $B0 -name $gfid_file3.2 | xargs stat -c %s`
 
-TEST $(dirname $0)/zero-flag $H0 $V0 "0" "5242880" "1048576" /file3
+TEST $(dirname $0)/zero-flag $H0 $V0 "0" "5242880" "1048576" /file3 `gluster --print-logdir`/glfs-$V0.log
 EXPECT "$md5sum_file3" echo `md5sum $M0/file3 | awk '{print $1}'`
 
-TEST umount $M0
+EXPECT_WITHIN $UMOUNT_TIMEOUT "Y" force_umount $M0
 TEST $CLI volume stop $V0
 TEST $CLI volume delete $V0
 rm -f $(dirname $0)/zero-flag
diff --git a/tests/volume.rc b/tests/volume.rc
index 3a98b87ef70..e488aa73b1c 100644
--- a/tests/volume.rc
+++ b/tests/volume.rc
@@ -655,3 +655,7 @@ function get_gfid_string {
         getfattr -n glusterfs.gfid.string $1 2>/dev/null \
                     | grep glusterfs.gfid.string | cut -d '"' -f 2
 }
+
+function file_all_zeroes {
+        < $1 tr -d '\0' | read -n 1 || echo 1
+}
diff --git a/xlators/features/shard/src/shard.c b/xlators/features/shard/src/shard.c
index 8e4443535e9..154411682f3 100644
--- a/xlators/features/shard/src/shard.c
+++ b/xlators/features/shard/src/shard.c
@@ -502,6 +502,10 @@ shard_common_inode_write_failure_unwind (glusterfs_fop_t fop,
                 SHARD_STACK_UNWIND (zerofill, frame, op_ret, op_errno,
                                     NULL, NULL, NULL);
                 break;
+        case GF_FOP_DISCARD:
+                SHARD_STACK_UNWIND (discard, frame, op_ret, op_errno,
+                                    NULL, NULL, NULL);
+                break;
         default:
                 gf_msg (THIS->name, GF_LOG_WARNING, 0, SHARD_MSG_INVALID_FOP,
                         "Invalid fop id = %d", fop);
@@ -531,6 +535,10 @@ shard_common_inode_write_success_unwind (glusterfs_fop_t fop,
                 SHARD_STACK_UNWIND (zerofill, frame, op_ret, 0, &local->prebuf,
                                     &local->postbuf, local->xattr_rsp);
                 break;
+        case GF_FOP_DISCARD:
+                SHARD_STACK_UNWIND (discard, frame, op_ret, 0, &local->prebuf,
+                                    &local->postbuf, local->xattr_rsp);
+                break;
         default:
                 gf_msg (THIS->name, GF_LOG_WARNING, 0, SHARD_MSG_INVALID_FOP,
                         "Invalid fop id = %d", fop);
@@ -3556,6 +3564,12 @@ shard_common_inode_write_wind (call_frame_t *frame, xlator_t *this,
                                    FIRST_CHILD(this)->fops->zerofill, fd,
                                    shard_offset, size, local->xattr_req);
                 break;
+        case GF_FOP_DISCARD:
+                STACK_WIND_COOKIE (frame, shard_common_inode_write_do_cbk, fd,
+                                   FIRST_CHILD(this),
+                                   FIRST_CHILD(this)->fops->discard, fd,
+                                   shard_offset, size, local->xattr_req);
+                break;
         default:
                 gf_msg (this->name, GF_LOG_WARNING, 0, SHARD_MSG_INVALID_FOP,
                         "Invalid fop id = %d", local->fop);
@@ -4502,6 +4516,11 @@ shard_common_inode_write_begin (call_frame_t *frame, xlator_t *this,
                                          FIRST_CHILD(this)->fops->zerofill,
                                          fd, offset, len, xdata);
                         break;
+                case GF_FOP_DISCARD:
+                        STACK_WIND_TAIL (frame, FIRST_CHILD(this),
+                                         FIRST_CHILD(this)->fops->discard,
+                                         fd, offset, len, xdata);
+                        break;
                 default:
                 gf_msg (this->name, GF_LOG_WARNING, 0, SHARD_MSG_INVALID_FOP,
                         "Invalid fop id = %d", fop);
@@ -4614,12 +4633,10 @@ shard_zerofill (call_frame_t *frame, xlator_t *this, fd_t *fd, off_t offset,
 
 int
 shard_discard (call_frame_t *frame, xlator_t *this, fd_t *fd, off_t offset,
-              size_t len, dict_t *xdata)
+               size_t len, dict_t *xdata)
 {
-        /* TBD */
-        gf_msg (this->name, GF_LOG_INFO, ENOTSUP, SHARD_MSG_FOP_NOT_SUPPORTED,
-                "discard called on %s.", uuid_utoa (fd->inode->gfid));
-        SHARD_STACK_UNWIND (discard, frame, -1, ENOTSUP, NULL, NULL, NULL);
+        shard_common_inode_write_begin (frame, this, GF_FOP_DISCARD, fd, NULL,
+                                        0, offset, 0, len, NULL, xdata);
         return 0;
 }