[JFFS2][XATTR] using 'delete marker' for xdatum/xref deletion

- When xdatum is removed, a new xdatum with 'delete marker' is
  written. (version==0xffffffff means 'delete marker')
- When xref is removed, a new xref with 'delete marker' is written.
  (odd-numbered xseqno means 'delete marker')

- delete_xattr_(datum/xref)_delay() are new deletion functions
  are added. We can only use them if we can detect the target
  obsolete xdatum/xref as a orphan or errir one.
  (e.g when inode deletion, or detecting crc error)

[1/3] jffs2-xattr-v6-01-delete_marker.patch

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

1 files changed, 14 insertions, 25 deletions

diff --git a/fs/jffs2/summary.c b/fs/jffs2/summary.c
index 0b02fc79e4d1..c430f1d217e2 100644
--- a/fs/jffs2/summary.c
+++ b/fs/jffs2/summary.c
@@ -310,8 +310,6 @@ int jffs2_sum_add_kvec(struct jffs2_sb_info *c, const struct kvec *invecs,
 #ifdef CONFIG_JFFS2_FS_XATTR
                 case JFFS2_NODETYPE_XATTR: {
                         struct jffs2_sum_xattr_mem *temp;
-                        if (je32_to_cpu(node->x.version) == 0xffffffff)
-                                return 0;
                         temp = kmalloc(sizeof(struct jffs2_sum_xattr_mem), GFP_KERNEL);
                         if (!temp)
                                 goto no_mem;
@@ -327,10 +325,6 @@ int jffs2_sum_add_kvec(struct jffs2_sb_info *c, const struct kvec *invecs,
                 }
                 case JFFS2_NODETYPE_XREF: {
                         struct jffs2_sum_xref_mem *temp;
-
-                        if (je32_to_cpu(node->r.ino) == 0xffffffff
-                            && je32_to_cpu(node->r.xid) == 0xffffffff)
-                                return 0;
                         temp = kmalloc(sizeof(struct jffs2_sum_xref_mem), GFP_KERNEL);
                         if (!temp)
                                 goto no_mem;
@@ -483,22 +477,20 @@ static int jffs2_sum_process_sum_data(struct jffs2_sb_info *c, struct jffs2_eras
 
                                 xd = jffs2_setup_xattr_datum(c, je32_to_cpu(spx->xid),
                                                                 je32_to_cpu(spx->version));
-                                if (IS_ERR(xd)) {
-                                        if (PTR_ERR(xd) == -EEXIST) {
-                                                /* a newer version of xd exists */
-                                                if ((err = jffs2_scan_dirty_space(c, jeb, je32_to_cpu(spx->totlen))))
-                                                        return err;
-                                                sp += JFFS2_SUMMARY_XATTR_SIZE;
-                                                break;
-                                        }
-                                        JFFS2_NOTICE("allocation of xattr_datum failed\n");
+                                if (IS_ERR(xd))
                                         return PTR_ERR(xd);
+                                if (xd->version > je32_to_cpu(spx->version)) {
+                                        /* node is not the newest one */
+                                        struct jffs2_raw_node_ref *raw
+                                                = sum_link_node_ref(c, jeb, je32_to_cpu(spx->offset) | REF_UNCHECKED,
+                                                                    PAD(je32_to_cpu(spx->totlen)), NULL);
+                                        raw->next_in_ino = xd->node->next_in_ino;
+                                        xd->node->next_in_ino = raw;
+                                } else {
+                                        xd->version = je32_to_cpu(spx->version);
+                                        sum_link_node_ref(c, jeb, je32_to_cpu(spx->offset) | REF_UNCHECKED,
+                                                          PAD(je32_to_cpu(spx->totlen)), (void *)xd);
                                 }
-
-                                xd->node = sum_link_node_ref(c, jeb, je32_to_cpu(spx->offset) | REF_UNCHECKED,
-                                                             PAD(je32_to_cpu(spx->totlen)), NULL);
-                                /* FIXME */ xd->node->next_in_ino = (void *)xd;
-
                                 *pseudo_random += je32_to_cpu(spx->xid);
                                 sp += JFFS2_SUMMARY_XATTR_SIZE;
 
@@ -519,14 +511,11 @@ static int jffs2_sum_process_sum_data(struct jffs2_sb_info *c, struct jffs2_eras
                                         JFFS2_NOTICE("allocation of xattr_datum failed\n");
                                         return -ENOMEM;
                                 }
-                                ref->ino = 0xfffffffe;
-                                ref->xid = 0xfffffffd;
                                 ref->next = c->xref_temp;
                                 c->xref_temp = ref;
 
-                                ref->node = sum_link_node_ref(c, jeb, je32_to_cpu(spr->offset) | REF_UNCHECKED,
-                                                              PAD(sizeof(struct jffs2_raw_xref)), NULL);
-                                /* FIXME */ ref->node->next_in_ino = (void *)ref;
+                                sum_link_node_ref(c, jeb, je32_to_cpu(spr->offset) | REF_UNCHECKED,
+                                                  PAD(sizeof(struct jffs2_raw_xref)), (void *)ref);
 
                                 *pseudo_random += ref->node->flash_offset;
                                 sp += JFFS2_SUMMARY_XREF_SIZE;