ocfs2: Remove xattrs via ocfs2_xa_loc

Add ocfs2_xa_remove_entry(), which will remove an xattr entry from its
storage via the ocfs2_xa_loc descriptor.

Signed-off-by: Joel Becker <joel.becker@oracle.com>

1 files changed, 29 insertions, 33 deletions

diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index 945ca697eb25..22a60a7c35ca 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -1573,7 +1573,29 @@ static const struct ocfs2_xa_loc_operations ocfs2_xa_bucket_loc_ops = {
 
 static void ocfs2_xa_remove_entry(struct ocfs2_xa_loc *loc)
 {
+        int index, count;
+        struct ocfs2_xattr_header *xh = loc->xl_header;
+        struct ocfs2_xattr_entry *entry = loc->xl_entry;
+
         ocfs2_xa_wipe_namevalue(loc);
+        loc->xl_entry = NULL;
+
+        le16_add_cpu(&xh->xh_count, -1);
+        count = le16_to_cpu(xh->xh_count);
+
+        /*
+         * Only zero out the entry if there are more remaining.  This is
+         * important for an empty bucket, as it keeps track of the
+         * bucket's hash value.  It doesn't hurt empty block storage.
+         */
+        if (count) {
+                index = ((char *)entry - (char *)&xh->xh_entries) /
+                        sizeof(struct ocfs2_xattr_entry);
+                memmove(&xh->xh_entries[index], &xh->xh_entries[index + 1],
+                        (count - index) * sizeof(struct ocfs2_xattr_entry));
+                memset(&xh->xh_entries[count], 0,
+                       sizeof(struct ocfs2_xattr_entry));
+        }
 }
 
 static void ocfs2_init_dinode_xa_loc(struct ocfs2_xa_loc *loc,
@@ -1638,7 +1660,6 @@ static void ocfs2_xattr_set_entry_local(struct inode *inode,
                                         size_t min_offs)
 {
         size_t name_len = strlen(xi->name);
-        int i;
         struct ocfs2_xa_loc loc;
 
         if (xs->xattr_bh == xs->inode_bh)
@@ -1686,25 +1707,12 @@ static void ocfs2_xattr_set_entry_local(struct inode *inode,
                         return;
                 }
 
-                /* Remove the old name+value. */
-                ocfs2_xa_wipe_namevalue(&loc);
-                xs->here->xe_name_hash = 0;
-                xs->here->xe_name_offset = 0;
-                ocfs2_xattr_set_local(xs->here, 1);
-                xs->here->xe_value_size = 0;
+                if (!xi->value)
+                        ocfs2_xa_remove_entry(&loc);
+                else
+                        ocfs2_xa_wipe_namevalue(&loc);
 
                 min_offs += size;
-
-                if (!xi->value) {
-                        /* Remove the old entry. */
-                        i = le16_to_cpu(xs->header->xh_count) - 1;
-                        last = &xs->header->xh_entries[i];
-                        xs->header->xh_count = cpu_to_le16(i);
-
-                        memmove(xs->here, xs->here + 1,
-                                (void *)last - (void *)xs->here);
-                        memset(last, 0, sizeof(struct ocfs2_xattr_entry));
-                }
         }
         if (xi->value) {
                 /* Insert the new name+value. */
@@ -5001,8 +5009,8 @@ static void ocfs2_xattr_set_entry_normal(struct inode *inode,
                 new_size = OCFS2_XATTR_SIZE(name_len) +
                            OCFS2_XATTR_SIZE(xi->value_len);
 
-                ocfs2_xa_wipe_namevalue(&loc);
                 if (xi->value) {
+                        ocfs2_xa_wipe_namevalue(&loc);
                         if (new_size > size)
                                 goto set_new_name_value;
 
@@ -5024,20 +5032,8 @@ static void ocfs2_xattr_set_entry_normal(struct inode *inode,
                         ocfs2_xattr_set_local(xe, local);
                         return;
                 } else {
-                        /*
-                         * Remove the old entry if there is more than one.
-                         * We don't remove the last entry so that we can
-                         * use it to indicate the hash value of the empty
-                         * bucket.
-                         */
-                        last -= 1;
-                        le16_add_cpu(&xh->xh_count, -1);
-                        if (xh->xh_count) {
-                                memmove(xe, xe + 1,
-                                        (void *)last - (void *)xe);
-                                memset(last, 0,
-                                       sizeof(struct ocfs2_xattr_entry));
-                        } else
+                        ocfs2_xa_remove_entry(&loc);
+                        if (!xh->xh_count)
                                 xh->xh_free_start =
                                         cpu_to_le16(OCFS2_XATTR_BUCKET_SIZE);