[JFFS2][XATTR] rid unnecessary writing of delete marker.

In the followinf situation, an explicit delete marker is not
necessary, because we can certainlly detect those obsolete
xattr_datum or xattr_ref on next mounting.

- When to delete xattr_datum node.
- When to delete xattr_ref node on removing inode.
- When to delete xattr_ref node on updating xattr.

This patch rids writing delete marker in those situations.

Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 102 insertions, 201 deletions

diff --git a/fs/jffs2/xattr.c b/fs/jffs2/xattr.c
index 03871ab7c26d..7622f79cb5b4 100644
--- a/fs/jffs2/xattr.c
+++ b/fs/jffs2/xattr.c
@@ -50,12 +50,9 @@
  *   is used to write xdatum to medium. xd->version will be incremented.
  * create_xattr_datum(c, xprefix, xname, xvalue, xsize)
  *   is used to create new xdatum and write to medium.
- * delete_xattr_datum_delay(c, xd)
- *   is used to delete a xdatum without 'delete marker'. It has a possibility to detect
- *   orphan xdatum on next mounting.
  * delete_xattr_datum(c, xd)
- *   is used to delete a xdatum with 'delete marker'. Calling jffs2_reserve_space() is
- *   necessary before this function.
+ *   is used to delete a xdatum. It marks xd JFFS2_XFLAGS_DEAD, and allows
+ *   GC to reclaim those physical nodes.
  * -------------------------------------------------- */
 static uint32_t xattr_datum_hashkey(int xprefix, const char *xname, const char *xvalue, int xsize)
 {
@@ -154,10 +151,7 @@ static int do_verify_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_dat
                 xd->flags |= JFFS2_XFLAGS_INVALID;
                 return EIO;
         }
-        totlen = sizeof(rx);
-        if (xd->version != XDATUM_DELETE_MARKER)
-                totlen += rx.name_len + 1 + je16_to_cpu(rx.value_len);
-        totlen = PAD(totlen);
+        totlen = PAD(sizeof(rx) + rx.name_len + 1 + je16_to_cpu(rx.value_len));
         if (je16_to_cpu(rx.magic) != JFFS2_MAGIC_BITMASK
             || je16_to_cpu(rx.nodetype) != JFFS2_NODETYPE_XATTR
             || je32_to_cpu(rx.totlen) != totlen
@@ -268,6 +262,7 @@ static int load_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *x
          */
         int rc = 0;
 
+        BUG_ON(xd->flags & JFFS2_XFLAGS_DEAD);
         if (xd->xname)
                 return 0;
         if (xd->flags & JFFS2_XFLAGS_INVALID)
@@ -285,20 +280,18 @@ static int save_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *x
         struct jffs2_raw_xattr rx;
         struct kvec vecs[2];
         size_t length;
-        int rc, totlen, nvecs = 1;
+        int rc, totlen;
         uint32_t phys_ofs = write_ofs(c);
 
-        BUG_ON(is_xattr_datum_dead(xd) || (xd->flags & JFFS2_XFLAGS_INVALID)
-               ? !!xd->xname : !xd->xname);
+        BUG_ON(!xd->xname);
+        BUG_ON(xd->flags & (JFFS2_XFLAGS_DEAD|JFFS2_XFLAGS_INVALID));
 
         vecs[0].iov_base = ℞
-        vecs[0].iov_len = totlen = sizeof(rx);
-        if (!is_xattr_datum_dead(xd) && !(xd->flags & JFFS2_XFLAGS_INVALID)) {
-                nvecs++;
-                vecs[1].iov_base = xd->xname;
-                vecs[1].iov_len = xd->name_len + 1 + xd->value_len;
-                totlen += vecs[1].iov_len;
-        }
+        vecs[0].iov_len = sizeof(rx);
+        vecs[1].iov_base = xd->xname;
+        vecs[1].iov_len = xd->name_len + 1 + xd->value_len;
+        totlen = vecs[0].iov_len + vecs[1].iov_len;
+
         /* Setup raw-xattr */
         memset(&rx, 0, sizeof(rx));
         rx.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
@@ -307,18 +300,14 @@ static int save_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *x
         rx.hdr_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_unknown_node) - 4));
 
         rx.xid = cpu_to_je32(xd->xid);
-        if (!is_xattr_datum_dead(xd) && !(xd->flags & JFFS2_XFLAGS_INVALID)) {
-                rx.version = cpu_to_je32(++xd->version);
-                rx.xprefix = xd->xprefix;
-                rx.name_len = xd->name_len;
-                rx.value_len = cpu_to_je16(xd->value_len);
-                rx.data_crc = cpu_to_je32(crc32(0, vecs[1].iov_base, vecs[1].iov_len));
-        } else {
-                rx.version = cpu_to_je32(XDATUM_DELETE_MARKER);
-        }
+        rx.version = cpu_to_je32(++xd->version);
+        rx.xprefix = xd->xprefix;
+        rx.name_len = xd->name_len;
+        rx.value_len = cpu_to_je16(xd->value_len);
+        rx.data_crc = cpu_to_je32(crc32(0, vecs[1].iov_base, vecs[1].iov_len));
         rx.node_crc = cpu_to_je32(crc32(0, &rx, sizeof(struct jffs2_raw_xattr) - 4));
 
-        rc = jffs2_flash_writev(c, vecs, nvecs, phys_ofs, &length, 0);
+        rc = jffs2_flash_writev(c, vecs, 2, phys_ofs, &length, 0);
         if (rc || totlen != length) {
                 JFFS2_WARNING("jffs2_flash_writev()=%d, req=%u, wrote=%zu, at %#08x\n",
                               rc, totlen, length, phys_ofs);
@@ -405,53 +394,36 @@ static struct jffs2_xattr_datum *create_xattr_datum(struct jffs2_sb_info *c,
         return xd;
 }
 
-static void delete_xattr_datum_delay(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
+static void delete_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
 {
         /* must be called under down_write(xattr_sem) */
         BUG_ON(xd->refcnt);
 
         unload_xattr_datum(c, xd);
-        set_xattr_datum_dead(xd);
+        xd->flags |= JFFS2_XFLAGS_DEAD;
         spin_lock(&c->erase_completion_lock);
-        list_add(&xd->xindex, &c->xattr_dead_list);
-        spin_unlock(&c->erase_completion_lock);
-        JFFS2_NOTICE("xdatum(xid=%u) was removed without delete marker. "
-                     "An orphan xdatum may be detected on next mounting.\n", xd->xid);
-}
-
-static void delete_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
-{
-        /* must be called under jffs2_reserve_space() and down_write(xattr_sem) */
-        int rc;
-        BUG_ON(xd->refcnt);
-
-        unload_xattr_datum(c, xd);
-        set_xattr_datum_dead(xd);       
-        rc = save_xattr_datum(c, xd);
-        if (rc) {
-                JFFS2_NOTICE("xdatum(xid=%u) was removed without delete marker. "
-                             "An orphan xdatum may be detected on next mounting.\n",
-                             xd->xid);
+        if (xd->node == (void *)xd) {
+                BUG_ON(!(xd->flags & JFFS2_XFLAGS_INVALID));
+                jffs2_free_xattr_datum(xd);
+        } else {
+                list_add(&xd->xindex, &c->xattr_dead_list);
         }
-        spin_lock(&c->erase_completion_lock);
-        list_add(&xd->xindex, &c->xattr_dead_list);
         spin_unlock(&c->erase_completion_lock);
+        dbg_xattr("xdatum(xid=%u, version=%u) was removed.\n", xd->xid, xd->version);
 }
 
 /* -------- xref related functions ------------------
  * verify_xattr_ref(c, ref)
  *   is used to load xref information from medium. Because summary data does not
  *   contain xid/ino, it's necessary to verify once while mounting process.
- * delete_xattr_ref_node(c, ref)
- *   is used to delete a jffs2 node is dominated by xref. When EBS is enabled,
- *   it overwrites the obsolete node by myself. 
- * delete_xattr_ref(c, ref)
- *   is used to delete jffs2_xattr_ref object. If the reference counter of xdatum
- *   is refered by this xref become 0, delete_xattr_datum() is called later.
  * save_xattr_ref(c, ref)
- *   is used to write xref to medium.
+ *   is used to write xref to medium. If delete marker is marked, it write
+ *   a delete marker of xref into medium.
  * create_xattr_ref(c, ic, xd)
  *   is used to create a new xref and write to medium.
+ * delete_xattr_ref(c, ref)
+ *   is used to delete jffs2_xattr_ref. It marks xref XREF_DELETE_MARKER,
+ *   and allows GC to reclaim those physical nodes.
  * jffs2_xattr_delete_inode(c, ic)
  *   is called to remove xrefs related to obsolete inode when inode is unlinked.
  * jffs2_xattr_free_inode(c, ic)
@@ -591,13 +563,13 @@ static struct jffs2_xattr_ref *create_xattr_ref(struct jffs2_sb_info *c, struct
         return ref; /* success */
 }
 
-static void delete_xattr_ref_delay(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
+static void delete_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref)
 {
         /* must be called under down_write(xattr_sem) */
         struct jffs2_xattr_datum *xd;
 
-        set_xattr_ref_dead(ref);
         xd = ref->xd;
+        ref->xseqno |= XREF_DELETE_MARKER;
         ref->ino = ref->ic->ino;
         ref->xid = ref->xd->xid;
         spin_lock(&c->erase_completion_lock);
@@ -605,102 +577,29 @@ static void delete_xattr_ref_delay(struct jffs2_sb_info *c, struct jffs2_xattr_r
         c->xref_dead_list = ref;
         spin_unlock(&c->erase_completion_lock);
 
-        JFFS2_NOTICE("xref(ino=%u, xid=%u) was removed without delete marker. "
-                     "An orphan xref may be detected on next mounting.\n",
-                     ref->ino, ref->xid);
+        dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) was removed.\n",
+                  ref->ino, ref->xid, ref->xseqno);
 
         if (!--xd->refcnt)
-                delete_xattr_datum_delay(c, xd);
-}
-
-static int delete_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref, int enforce)
-{
-        /* must be called under jffs2_reserve_space() and down_write(xattr_sem) */
-        struct jffs2_inode_cache *ic;
-        struct jffs2_xattr_datum *xd;
-        uint32_t length;
-        int rc;
-
-        set_xattr_ref_dead(ref);
-        ic = ref->ic;
-        xd = ref->xd;
-        ref->ino = ic->ino;
-        ref->xid = xd->xid;
-        rc = save_xattr_ref(c, ref);
-        if (rc) {
-                if (!enforce) {
-                        clr_xattr_ref_dead(ref);
-                        ref->ic = ic;
-                        ref->xd = xd;
-                        return rc;
-                }
-                JFFS2_WARNING("could not write delete marker of xref(ino=%u, xid=%u). "
-                              "An orphan xref may be detected on next mounting.\n",
-                              ref->ic->ino, ref->xd->xid);
-        }
-        spin_lock(&c->erase_completion_lock);
-        ref->next = c->xref_dead_list;
-        c->xref_dead_list = ref;
-        spin_unlock(&c->erase_completion_lock);
-
-        xd->refcnt--;
-        if (xd->refcnt)
-                return 0;
-
-        /* delete xdatum */
-        unload_xattr_datum(c, xd);
-        up_write(&c->xattr_sem);
-        jffs2_complete_reservation(c);
-
-        rc = jffs2_reserve_space(c, PAD(sizeof(struct jffs2_raw_xattr)), &length,
-                                 ALLOC_DELETION, JFFS2_SUMMARY_XATTR_SIZE);
-        if (rc) {
-                down(&c->alloc_sem);
-                down_write(&c->xattr_sem);
-                delete_xattr_datum_delay(c, xd);
-        } else {
-                down_write(&c->xattr_sem);
                 delete_xattr_datum(c, xd);
-        }
-        return 0;
 }
 
 void jffs2_xattr_delete_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
 {
         /* It's called from jffs2_clear_inode() on inode removing.
            When an inode with XATTR is removed, those XATTRs must be removed. */
-        struct jffs2_xattr_ref *ref;
-        uint32_t length;
-        int rc, retry;
+        struct jffs2_xattr_ref *ref, *_ref;
 
         if (!ic || ic->nlink > 0)
                 return;
 
-        down_read(&c->xattr_sem);
-        if (!ic->xref) {
-                up_read(&c->xattr_sem);
-                return;
-        }
-        up_read(&c->xattr_sem);
- retry:
-        rc = jffs2_reserve_space(c, PAD(sizeof(struct jffs2_raw_xref)), &length,
-                                 ALLOC_DELETION, JFFS2_SUMMARY_XREF_SIZE);
         down_write(&c->xattr_sem);
-        if (ic->xref) {
-                ref = ic->xref;
-                ic->xref = ref->next;
-                if (rc) {
-                        delete_xattr_ref_delay(c, ref);
-                } else {
-                        delete_xattr_ref(c, ref, 1);
-                }
+        for (ref = ic->xref; ref; ref = _ref) {
+                _ref = ref->next;
+                delete_xattr_ref(c, ref);
         }
-        retry = ic->xref ? 1 : 0;
+        ic->xref = NULL;
         up_write(&c->xattr_sem);
-        if (!rc)
-                jffs2_complete_reservation(c);
-        if (retry)
-                goto retry;
 }
 
 void jffs2_xattr_free_inode(struct jffs2_sb_info *c, struct jffs2_inode_cache *ic)
@@ -743,7 +642,7 @@ static int check_xattr_ref_inode(struct jffs2_sb_info *c, struct jffs2_inode_cac
                         rc = load_xattr_datum(c, ref->xd);
                         if (unlikely(rc > 0)) {
                                 *pref = ref->next;
-                                delete_xattr_ref_delay(c, ref);
+                                delete_xattr_ref(c, ref);
                                 goto retry;
                         } else if (unlikely(rc < 0))
                                 goto out;
@@ -755,7 +654,7 @@ static int check_xattr_ref_inode(struct jffs2_sb_info *c, struct jffs2_inode_cac
                                 ref->xd->flags &= ~JFFS2_XFLAGS_BIND;
                                 if (unlikely(rc > 0)) {
                                         *pcmp = cmp->next;
-                                        delete_xattr_ref_delay(c, cmp);
+                                        delete_xattr_ref(c, cmp);
                                         goto retry;
                                 } else if (unlikely(rc < 0))
                                         goto out;
@@ -764,10 +663,10 @@ static int check_xattr_ref_inode(struct jffs2_sb_info *c, struct jffs2_inode_cac
                             && !strcmp(ref->xd->xname, cmp->xd->xname)) {
                                 if (ref->xseqno > cmp->xseqno) {
                                         *pcmp = cmp->next;
-                                        delete_xattr_ref_delay(c, cmp);
+                                        delete_xattr_ref(c, cmp);
                                 } else {
                                         *pref = ref->next;
-                                        delete_xattr_ref_delay(c, ref);
+                                        delete_xattr_ref(c, ref);
                                 }
                                 goto retry;
                         }
@@ -865,20 +764,11 @@ void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
         struct jffs2_inode_cache *ic;
         struct jffs2_raw_node_ref *raw;
         int i, xdatum_count = 0, xdatum_unchecked_count = 0, xref_count = 0;
+        int xdatum_orphan_count = 0, xref_orphan_count = 0, xref_dead_count = 0;
 
         BUG_ON(!(c->flags & JFFS2_SB_FLAG_BUILDING));
-        /* Phase.1 : Drop dead xdatum */
-        for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
-                list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
-                        BUG_ON(xd->node == (void *)xd);
-                        if (is_xattr_datum_dead(xd)) {
-                                list_del_init(&xd->xindex);
-                                list_add(&xd->xindex, &c->xattr_unchecked);
-                        }
-                }
-        }
 
-        /* Phase.2 : Merge same xref */
+        /* Phase.1 : Merge same xref */
         for (i=0; i < XREF_TMPHASH_SIZE; i++)
                 xref_tmphash[i] = NULL;
         for (ref=c->xref_temp; ref; ref=_ref) {
@@ -919,13 +809,15 @@ void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
         }
         c->xref_temp = NULL;
 
-        /* Phase.3 : Bind xref with inode_cache and xattr_datum */
+        /* Phase.2 : Bind xref with inode_cache and xattr_datum */
         for (i=0; i < XREF_TMPHASH_SIZE; i++) {
                 for (ref=xref_tmphash[i]; ref; ref=_ref) {
+                        xref_count++;
                         _ref = ref->next;
                         if (is_xattr_ref_dead(ref)) {
                                 ref->next = c->xref_dead_list;
                                 c->xref_dead_list = ref;
+                                xref_dead_count++;
                                 continue;
                         }
                         /* At this point, ref->xid and ref->ino contain XID and inode number.
@@ -933,11 +825,12 @@ void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
                         xd = jffs2_find_xattr_datum(c, ref->xid);
                         ic = jffs2_get_ino_cache(c, ref->ino);
                         if (!xd || !ic) {
-                                JFFS2_WARNING("xref(ino=%u, xid=%u, xseqno=%u) is orphan. \n",
-                                              ref->ino, ref->xid, ref->xseqno);
-                                set_xattr_ref_dead(ref);
+                                dbg_xattr("xref(ino=%u, xid=%u, xseqno=%u) is orphan.\n",
+                                          ref->ino, ref->xid, ref->xseqno);
+                                ref->xseqno |= XREF_DELETE_MARKER;
                                 ref->next = c->xref_dead_list;
                                 c->xref_dead_list = ref;
+                                xref_orphan_count++;
                                 continue;
                         }
                         ref->xd = xd;
@@ -945,19 +838,20 @@ void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
                         xd->refcnt++;
                         ref->next = ic->xref;
                         ic->xref = ref;
-                        xref_count++;
                 }
         }
 
-        /* Phase.4 : Link unchecked xdatum to xattr_unchecked list */
+        /* Phase.3 : Link unchecked xdatum to xattr_unchecked list */
         for (i=0; i < XATTRINDEX_HASHSIZE; i++) {
                 list_for_each_entry_safe(xd, _xd, &c->xattrindex[i], xindex) {
+                        xdatum_count++;
                         list_del_init(&xd->xindex);
                         if (!xd->refcnt) {
-                                JFFS2_WARNING("orphan xdatum(xid=%u, version=%u)\n",
-                                              xd->xid, xd->version);
-                                set_xattr_datum_dead(xd);
+                                dbg_xattr("xdatum(xid=%u, version=%u) is orphan.\n",
+                                          xd->xid, xd->version);
+                                xd->flags |= JFFS2_XFLAGS_DEAD;
                                 list_add(&xd->xindex, &c->xattr_unchecked);
+                                xdatum_orphan_count++;
                                 continue;
                         }
                         if (is_xattr_datum_unchecked(c, xd)) {
@@ -966,12 +860,14 @@ void jffs2_build_xattr_subsystem(struct jffs2_sb_info *c)
                                 list_add(&xd->xindex, &c->xattr_unchecked);
                                 xdatum_unchecked_count++;
                         }
-                        xdatum_count++;
                 }
         }
         /* build complete */
-        JFFS2_NOTICE("complete building xattr subsystem, %u of xdatum (%u unchecked) and "
-                     "%u of xref found.\n", xdatum_count, xdatum_unchecked_count, xref_count);
+        JFFS2_NOTICE("complete building xattr subsystem, %u of xdatum"
+                     " (%u unchecked, %u orphan) and "
+                     "%u of xref (%u dead, %u orphan) found.\n",
+                     xdatum_count, xdatum_unchecked_count, xdatum_orphan_count,
+                     xref_count, xref_dead_count, xref_orphan_count);
 }
 
 struct jffs2_xattr_datum *jffs2_setup_xattr_datum(struct jffs2_sb_info *c,
@@ -1079,7 +975,7 @@ ssize_t jffs2_listxattr(struct dentry *dentry, char *buffer, size_t size)
                                 rc = load_xattr_datum(c, xd);
                                 if (unlikely(rc > 0)) {
                                         *pref = ref->next;
-                                        delete_xattr_ref_delay(c, ref);
+                                        delete_xattr_ref(c, ref);
                                         goto retry;
                                 } else if (unlikely(rc < 0))
                                         goto out;
@@ -1140,7 +1036,7 @@ int do_jffs2_getxattr(struct inode *inode, int xprefix, const char *xname,
                                 rc = load_xattr_datum(c, xd);
                                 if (unlikely(rc > 0)) {
                                         *pref = ref->next;
-                                        delete_xattr_ref_delay(c, ref);
+                                        delete_xattr_ref(c, ref);
                                         goto retry;
                                 } else if (unlikely(rc < 0)) {
                                         goto out;
@@ -1203,7 +1099,7 @@ int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
                         rc = load_xattr_datum(c, xd);
                         if (unlikely(rc > 0)) {
                                 *pref = ref->next;
-                                delete_xattr_ref_delay(c, ref);
+                                delete_xattr_ref(c, ref);
                                 goto retry;
                         } else if (unlikely(rc < 0))
                                 goto out;
@@ -1214,8 +1110,23 @@ int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
                                 goto out;
                         }
                         if (!buffer) {
-                                *pref = ref->next;
-                                rc = delete_xattr_ref(c, ref, 0);
+                                ref->ino = ic->ino;
+                                ref->xid = xd->xid;
+                                ref->xseqno |= XREF_DELETE_MARKER;
+                                rc = save_xattr_ref(c, ref);
+                                if (!rc) {
+                                        *pref = ref->next;
+                                        spin_lock(&c->erase_completion_lock);
+                                        ref->next = c->xref_dead_list;
+                                        c->xref_dead_list = ref;
+                                        spin_unlock(&c->erase_completion_lock);
+                                        if (!--xd->refcnt)
+                                                delete_xattr_datum(c, xd);
+                                } else {
+                                        ref->ic = ic;
+                                        ref->xd = xd;
+                                        ref->xseqno &= ~XREF_DELETE_MARKER;
+                                }
                                 goto out;
                         }
                         goto found;
@@ -1248,7 +1159,7 @@ int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
                 JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
                 xd->refcnt--;
                 if (!xd->refcnt)
-                        delete_xattr_datum_delay(c, xd);
+                        delete_xattr_datum(c, xd);
                 up_write(&c->xattr_sem);
                 return rc;
         }
@@ -1263,21 +1174,9 @@ int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
                 rc = PTR_ERR(newref);
                 xd->refcnt--;
                 if (!xd->refcnt)
-                        delete_xattr_datum_delay(c, xd);
+                        delete_xattr_datum(c, xd);
         } else if (ref) {
-                up_write(&c->xattr_sem);
-                jffs2_complete_reservation(c);
-
-                rc = jffs2_reserve_space(c, request, &length,
-                                         ALLOC_DELETION, JFFS2_SUMMARY_XREF_SIZE);
-                down_write(&c->xattr_sem);
-                if (rc) {
-                        JFFS2_WARNING("jffs2_reserve_space()=%d, request=%u\n", rc, request);
-                        delete_xattr_ref_delay(c, ref);
-                        up_write(&c->xattr_sem);
-                        return 0;
-                }
-                delete_xattr_ref(c, ref, 1);
+                delete_xattr_ref(c, ref);
         }
  out:
         up_write(&c->xattr_sem);
@@ -1292,6 +1191,10 @@ int do_jffs2_setxattr(struct inode *inode, int xprefix, const char *xname,
  *   is used to move xref into new node.
  * jffs2_verify_xattr(c)
  *   is used to call do_verify_xattr_datum() before garbage collecting.
+ * jffs2_release_xattr_datum(c, xd)
+ *   is used to release an in-memory object of xdatum.
+ * jffs2_release_xattr_ref(c, ref)
+ *   is used to release an in-memory object of xref.
  * -------------------------------------------------- */
 int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd,
                                       struct jffs2_raw_node_ref *raw)
@@ -1302,18 +1205,17 @@ int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xatt
         down_write(&c->xattr_sem);
         if (xd->node != raw)
                 goto out;
-        if (is_xattr_datum_dead(xd) && (raw->next_in_ino == (void *)xd))
+        if (xd->flags & (JFFS2_XFLAGS_DEAD|JFFS2_XFLAGS_INVALID))
                 goto out;
 
-        old_ofs = ref_offset(xd->node);
-        totlen = ref_totlen(c, c->gcblock, xd->node);
-
-        if (!is_xattr_datum_dead(xd)) {
-                rc = load_xattr_datum(c, xd);
-                if (unlikely(rc < 0))
-                        goto out;
+        rc = load_xattr_datum(c, xd);
+        if (unlikely(rc)) {
+                rc = (rc > 0) ? 0 : rc;
+                goto out;
         }
-
+        old_ofs = ref_offset(xd->node);
+        totlen = PAD(sizeof(struct jffs2_raw_xattr)
+                        + xd->name_len + 1 + xd->value_len);
         rc = jffs2_reserve_space_gc(c, totlen, &length, JFFS2_SUMMARY_XATTR_SIZE);
         if (rc) {
                 JFFS2_WARNING("jffs2_reserve_space_gc()=%d, request=%u\n", rc, totlen);
@@ -1331,7 +1233,6 @@ int jffs2_garbage_collect_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xatt
         return rc;
 }
 
-
 int jffs2_garbage_collect_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *ref,
                                     struct jffs2_raw_node_ref *raw)
 {
@@ -1392,7 +1293,7 @@ int jffs2_verify_xattr(struct jffs2_sb_info *c)
                         raw->flash_offset = ref_offset(raw)
                                 | ((xd->node == (void *)raw) ? REF_PRISTINE : REF_NORMAL);
                 }
-                if (is_xattr_datum_dead(xd))
+                if (xd->flags & JFFS2_XFLAGS_DEAD)
                         list_add(&xd->xindex, &c->xattr_dead_list);
                 spin_unlock(&c->erase_completion_lock);
         }
@@ -1403,7 +1304,7 @@ int jffs2_verify_xattr(struct jffs2_sb_info *c)
 void jffs2_release_xattr_datum(struct jffs2_sb_info *c, struct jffs2_xattr_datum *xd)
 {
         /* must be called under spin_lock(&c->erase_completion_lock) */
-        if (xd->node != (void *)xd)
+        if (xd->refcnt > 0 || xd->node != (void *)xd)
                 return;
 
         list_del(&xd->xindex);
@@ -1421,8 +1322,8 @@ void jffs2_release_xattr_ref(struct jffs2_sb_info *c, struct jffs2_xattr_ref *re
         for (tmp=c->xref_dead_list, ptmp=&c->xref_dead_list; tmp; ptmp=&tmp->next, tmp=tmp->next) {
                 if (ref == tmp) {
                         *ptmp = tmp->next;
-                        jffs2_free_xattr_ref(ref);
                         break;
                 }
         }
+        jffs2_free_xattr_ref(ref);
 }