ctime: Set mdata xattr on legacy files

Problem:
The files which were created before ctime enabled would not
have "trusted.glusterfs.mdata"(stores time attributes) xattr.
Upon fops which modifies either ctime or mtime, the xattr
gets created with latest ctime, mtime and atime, which is
incorrect. It should update only the corresponding time
attribute and rest from backend

Solution:
Creating xattr with values from brick is not possible as
each brick of replica set would have different times.
So create the xattr upon successful lookup if the xattr
is not created

Note To Reviewers:
The time attributes used to set xattr is got from successful
lookup. Instead of sending the whole iatt over the wire via
setxattr, a structure called mdata_iatt is sent. The mdata_iatt
contains only time attributes.

Change-Id: I5e535631ddef04195361ae0364336410a2895dd4
fixes: bz#1593542
Signed-off-by: Kotresh HR <khiremat@redhat.com>

1 files changed, 59 insertions, 0 deletions

diff --git a/libglusterfs/src/dict.c b/libglusterfs/src/dict.c
index 2a317e36981..b44dda33f00 100644
--- a/libglusterfs/src/dict.c
+++ b/libglusterfs/src/dict.c
@@ -118,6 +118,7 @@ int32_t
 is_data_equal(data_t *one, data_t *two)
 {
     struct iatt *iatt1, *iatt2;
+    struct mdata_iatt *mdata_iatt1, *mdata_iatt2;
 
     if (!one || !two || !one->data || !two->data) {
         gf_msg_callingfn("dict", GF_LOG_ERROR, EINVAL, LG_MSG_INVALID_ARG,
@@ -182,6 +183,24 @@ is_data_equal(data_t *one, data_t *two)
         */
         return 1;
     }
+    if (one->data_type == GF_DATA_TYPE_MDATA) {
+        if ((one->len < sizeof(struct mdata_iatt)) ||
+            (two->len < sizeof(struct mdata_iatt))) {
+            return 0;
+        }
+        mdata_iatt1 = (struct mdata_iatt *)one->data;
+        mdata_iatt2 = (struct mdata_iatt *)two->data;
+
+        if (mdata_iatt1->ia_atime != mdata_iatt2->ia_atime ||
+            mdata_iatt1->ia_mtime != mdata_iatt2->ia_mtime ||
+            mdata_iatt1->ia_ctime != mdata_iatt2->ia_ctime ||
+            mdata_iatt1->ia_atime_nsec != mdata_iatt2->ia_atime_nsec ||
+            mdata_iatt1->ia_mtime_nsec != mdata_iatt2->ia_mtime_nsec ||
+            mdata_iatt1->ia_ctime_nsec != mdata_iatt2->ia_ctime_nsec) {
+            return 0;
+        }
+        return 1;
+    }
 
     if (one->len != two->len)
         return 0;
@@ -1072,6 +1091,7 @@ static char *data_type_name[GF_DATA_TYPE_MAX] = {
     [GF_DATA_TYPE_PTR] = "pointer",
     [GF_DATA_TYPE_GFUUID] = "gf-uuid",
     [GF_DATA_TYPE_IATT] = "iatt",
+    [GF_DATA_TYPE_MDATA] = "mdata",
 };
 
 int64_t
@@ -2660,6 +2680,45 @@ err:
 }
 
 int
+dict_set_mdata(dict_t *this, char *key, struct mdata_iatt *mdata,
+               bool is_static)
+{
+    return dict_set_bin_common(this, key, mdata, sizeof(struct mdata_iatt),
+                               is_static, GF_DATA_TYPE_MDATA);
+}
+
+int
+dict_get_mdata(dict_t *this, char *key, struct mdata_iatt *mdata)
+{
+    data_t *data = NULL;
+    int ret = -EINVAL;
+
+    if (!this || !key || !mdata) {
+        goto err;
+    }
+    ret = dict_get_with_ref(this, key, &data);
+    if (ret < 0) {
+        goto err;
+    }
+
+    VALIDATE_DATA_AND_LOG(data, GF_DATA_TYPE_MDATA, key, -EINVAL);
+    if (data->len < sizeof(struct mdata_iatt)) {
+        gf_msg("glusterfs", GF_LOG_ERROR, ENOBUFS, LG_MSG_UNDERSIZED_BUF,
+               "data value for '%s' is smaller than expected", key);
+        ret = -ENOBUFS;
+        goto err;
+    }
+
+    memcpy(mdata, data->data, min(data->len, sizeof(struct mdata_iatt)));
+
+err:
+    if (data)
+        data_unref(data);
+
+    return ret;
+}
+
+int
 dict_set_iatt(dict_t *this, char *key, struct iatt *iatt, bool is_static)
 {
     return dict_set_bin_common(this, key, iatt, sizeof(struct iatt), is_static,