storage/posix: New gfid2path infra

With this infra, a new xattr is stored on each entry
creation as below.

trusted.gfid2path.<xxhash> = <pargfid>/<basename>

If there are hardlinks, multiple xattrs would be present.

Fops which are impacted:
create, mknod, link, symlink, rename, unlink

Option to enable:
gluster vol set <VOLNAME> storage.gfid2path on

Updates: #139
Change-Id: I369974cd16703c45ee87f82e6c2ff5a987a6cc6a
Signed-off-by: Kotresh HR <khiremat@redhat.com>
Reviewed-on: https://review.gluster.org/17488
Smoke: Gluster Build System <jenkins@build.gluster.org>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Aravinda VK <avishwan@redhat.com>
Reviewed-by: Amar Tumballi <amarts@redhat.com>

1 files changed, 85 insertions, 0 deletions

diff --git a/xlators/storage/posix/src/posix-gfid-path.c b/xlators/storage/posix/src/posix-gfid-path.c
new file mode 100644
index 00000000000..500f4d81c24
--- /dev/null
+++ b/xlators/storage/posix/src/posix-gfid-path.c
@@ -0,0 +1,85 @@
+/*
+   Copyright (c) 2017 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 "common-utils.h"
+#include "xlator.h"
+#include "syscall.h"
+#include "logging.h"
+#include "posix-messages.h"
+
+int32_t
+posix_set_gfid2path_xattr (xlator_t *this, const char *path, uuid_t pgfid,
+                           const char *bname)
+{
+        char        xxh64[GF_XXH64_DIGEST_LENGTH*2+1] = {0,};
+        char        pgfid_bname[1024]                 = {0,};
+        char       *key                               = NULL;
+        char       *val                               = NULL;
+        size_t      key_size                          = 0;
+        size_t      val_size                          = 0;
+        int         ret                               = 0;
+
+        GF_VALIDATE_OR_GOTO ("posix", this, err);
+
+        snprintf (pgfid_bname, sizeof (pgfid_bname), "%s/%s", uuid_utoa (pgfid),
+                  bname);
+        gf_xxh64_wrapper ((unsigned char *) pgfid_bname,
+                          strlen(pgfid_bname), GF_XXHSUM64_DEFAULT_SEED, xxh64);
+        key_size = strlen(GFID2PATH_XATTR_KEY_PREFIX) + GF_XXH64_DIGEST_LENGTH*2+1;
+        key = alloca (key_size);
+        snprintf (key, key_size, GFID2PATH_XATTR_KEY_PREFIX"%s", xxh64);
+
+        val_size = UUID_CANONICAL_FORM_LEN + NAME_MAX + 2;
+        val = alloca (val_size);
+        snprintf (val, val_size, "%s/%s", uuid_utoa (pgfid), bname);
+
+        ret = sys_lsetxattr (path, key, val, strlen(val), XATTR_CREATE);
+        if (ret == -1) {
+                gf_msg (this->name, GF_LOG_WARNING, errno, P_MSG_PGFID_OP,
+                        "setting gfid2path xattr failed on %s: key = %s ",
+                        path, key);
+                goto err;
+        }
+        return 0;
+ err:
+        return -1;
+}
+
+int32_t
+posix_remove_gfid2path_xattr (xlator_t *this, const char *path,
+                              uuid_t pgfid, const char *bname)
+{
+        char        xxh64[GF_XXH64_DIGEST_LENGTH*2+1] = {0,};
+        char        pgfid_bname[1024]                 = {0,};
+        int         ret                               = 0;
+        char       *key                               = NULL;
+        size_t      key_size                          = 0;
+
+        GF_VALIDATE_OR_GOTO ("posix", this, err);
+
+        snprintf (pgfid_bname, sizeof (pgfid_bname), "%s/%s", uuid_utoa (pgfid),
+                  bname);
+        gf_xxh64_wrapper ((unsigned char *) pgfid_bname,
+                          strlen(pgfid_bname), GF_XXHSUM64_DEFAULT_SEED, xxh64);
+        key_size = strlen(GFID2PATH_XATTR_KEY_PREFIX) + GF_XXH64_DIGEST_LENGTH*2+1;
+        key = alloca (key_size);
+        snprintf (key, key_size, GFID2PATH_XATTR_KEY_PREFIX"%s", xxh64);
+
+        ret = sys_lremovexattr (path, key);
+        if (ret == -1) {
+                gf_msg (this->name, GF_LOG_WARNING, errno, P_MSG_PGFID_OP,
+                        "removing gfid2path xattr failed on %s: key = %s",
+                        path, key);
+                goto err;
+        }
+        return 0;
+ err:
+        return -1;
+}