UBIFS: introduce LPT dump function

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

5 files changed, 186 insertions, 48 deletions

diff --git a/fs/ubifs/debug.c b/fs/ubifs/debug.c
index 56842772c804..934db1855f09 100644
--- a/fs/ubifs/debug.c
+++ b/fs/ubifs/debug.c
@@ -646,7 +646,8 @@ void dbg_dump_lprops(struct ubifs_info *c)
         struct ubifs_lprops lp;
         struct ubifs_lp_stats lst;
 
-        printk(KERN_DEBUG "(pid %d) Dumping LEB properties\n", current->pid);
+        printk(KERN_DEBUG "(pid %d) start dumping LEB properties\n",
+               current->pid);
         ubifs_get_lp_stats(c, &lst);
         dbg_dump_lstats(&lst);
 
@@ -657,6 +658,8 @@ void dbg_dump_lprops(struct ubifs_info *c)
 
                 dbg_dump_lprop(c, &lp);
         }
+        printk(KERN_DEBUG "(pid %d) finish dumping LEB properties\n",
+               current->pid);
 }
 
 void dbg_dump_lpt_info(struct ubifs_info *c)
@@ -664,6 +667,7 @@ void dbg_dump_lpt_info(struct ubifs_info *c)
         int i;
 
         spin_lock(&dbg_lock);
+        printk(KERN_DEBUG "(pid %d) dumping LPT information\n", current->pid);
         printk(KERN_DEBUG "\tlpt_sz:        %lld\n", c->lpt_sz);
         printk(KERN_DEBUG "\tpnode_sz:      %d\n", c->pnode_sz);
         printk(KERN_DEBUG "\tnnode_sz:      %d\n", c->nnode_sz);
@@ -704,8 +708,8 @@ void dbg_dump_leb(const struct ubifs_info *c, int lnum)
         if (dbg_failure_mode)
                 return;
 
-        printk(KERN_DEBUG "(pid %d) Dumping LEB %d\n", current->pid, lnum);
-
+        printk(KERN_DEBUG "(pid %d) start dumping LEB %d\n",
+               current->pid, lnum);
         sleb = ubifs_scan(c, lnum, 0, c->dbg->buf);
         if (IS_ERR(sleb)) {
                 ubifs_err("scan error %d", (int)PTR_ERR(sleb));
@@ -722,6 +726,8 @@ void dbg_dump_leb(const struct ubifs_info *c, int lnum)
                 dbg_dump_node(c, snod->node);
         }
 
+        printk(KERN_DEBUG "(pid %d) finish dumping LEB %d\n",
+               current->pid, lnum);
         ubifs_scan_destroy(sleb);
         return;
 }
@@ -769,7 +775,7 @@ void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat)
 {
         int i;
 
-        printk(KERN_DEBUG "(pid %d) Dumping heap cat %d (%d elements)\n",
+        printk(KERN_DEBUG "(pid %d) start dumping heap cat %d (%d elements)\n",
                current->pid, cat, heap->cnt);
         for (i = 0; i < heap->cnt; i++) {
                 struct ubifs_lprops *lprops = heap->arr[i];
@@ -778,6 +784,7 @@ void dbg_dump_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat)
                        "flags %d\n", i, lprops->lnum, lprops->hpos,
                        lprops->free, lprops->dirty, lprops->flags);
         }
+        printk(KERN_DEBUG "(pid %d) finish dumping heap\n", current->pid);
 }
 
 void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
@@ -785,7 +792,7 @@ void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
 {
         int i;
 
-        printk(KERN_DEBUG "(pid %d) Dumping pnode:\n", current->pid);
+        printk(KERN_DEBUG "(pid %d) dumping pnode:\n", current->pid);
         printk(KERN_DEBUG "\taddress %zx parent %zx cnext %zx\n",
                (size_t)pnode, (size_t)parent, (size_t)pnode->cnext);
         printk(KERN_DEBUG "\tflags %lu iip %d level %d num %d\n",
@@ -804,7 +811,7 @@ void dbg_dump_tnc(struct ubifs_info *c)
         int level;
 
         printk(KERN_DEBUG "\n");
-        printk(KERN_DEBUG "(pid %d) Dumping the TNC tree\n", current->pid);
+        printk(KERN_DEBUG "(pid %d) start dumping TNC tree\n", current->pid);
         znode = ubifs_tnc_levelorder_next(c->zroot.znode, NULL);
         level = znode->level;
         printk(KERN_DEBUG "== Level %d ==\n", level);
@@ -816,8 +823,7 @@ void dbg_dump_tnc(struct ubifs_info *c)
                 dbg_dump_znode(c, znode);
                 znode = ubifs_tnc_levelorder_next(c->zroot.znode, znode);
         }
-
-        printk(KERN_DEBUG "\n");
+        printk(KERN_DEBUG "(pid %d) finish dumping TNC tree\n", current->pid);
 }
 
 static int dump_znode(struct ubifs_info *c, struct ubifs_znode *znode,
@@ -992,7 +998,8 @@ static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
                 ubifs_err("1st entry at %d:%d has key %s", zbr1->lnum,
                           zbr1->offs, DBGKEY(&key));
                 ubifs_err("but it should have key %s according to tnc",
-                          DBGKEY(&zbr1->key)); dbg_dump_node(c, dent1);
+                          DBGKEY(&zbr1->key));
+                dbg_dump_node(c, dent1);
                 goto out_free;
         }
 
@@ -1001,7 +1008,8 @@ static int dbg_check_key_order(struct ubifs_info *c, struct ubifs_zbranch *zbr1,
                 ubifs_err("2nd entry at %d:%d has key %s", zbr1->lnum,
                           zbr1->offs, DBGKEY(&key));
                 ubifs_err("but it should have key %s according to tnc",
-                          DBGKEY(&zbr2->key)); dbg_dump_node(c, dent2);
+                          DBGKEY(&zbr2->key));
+                dbg_dump_node(c, dent2);
                 goto out_free;
         }
 
diff --git a/fs/ubifs/debug.h b/fs/ubifs/debug.h
index a6b70f8aac9c..9820d6999f7e 100644
--- a/fs/ubifs/debug.h
+++ b/fs/ubifs/debug.h
@@ -270,6 +270,8 @@ const char *dbg_get_key_dump(const struct ubifs_info *c,
                              const union ubifs_key *key);
 void dbg_dump_inode(const struct ubifs_info *c, const struct inode *inode);
 void dbg_dump_node(const struct ubifs_info *c, const void *node);
+void dbg_dump_lpt_node(const struct ubifs_info *c, void *node, int lnum,
+                       int offs);
 void dbg_dump_budget_req(const struct ubifs_budget_req *req);
 void dbg_dump_lstats(const struct ubifs_lp_stats *lst);
 void dbg_dump_budg(struct ubifs_info *c);
@@ -284,6 +286,7 @@ void dbg_dump_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
                     struct ubifs_nnode *parent, int iip);
 void dbg_dump_tnc(struct ubifs_info *c);
 void dbg_dump_index(struct ubifs_info *c);
+void dbg_dump_lpt_lebs(const struct ubifs_info *c);
 
 /* Checking helper functions */
 typedef int (*dbg_leaf_callback)(struct ubifs_info *c,
@@ -411,26 +414,28 @@ void dbg_debugfs_exit_fs(struct ubifs_info *c);
 #define DBGKEY(key)  ((char *)(key))
 #define DBGKEY1(key) ((char *)(key))
 
-#define ubifs_debugging_init(c)               0
-#define ubifs_debugging_exit(c)               ({})
-
-#define dbg_ntype(type)                       ""
-#define dbg_cstate(cmt_state)                 ""
-#define dbg_get_key_dump(c, key)              ({})
-#define dbg_dump_inode(c, inode)              ({})
-#define dbg_dump_node(c, node)                ({})
-#define dbg_dump_budget_req(req)              ({})
-#define dbg_dump_lstats(lst)                  ({})
-#define dbg_dump_budg(c)                      ({})
-#define dbg_dump_lprop(c, lp)                 ({})
-#define dbg_dump_lprops(c)                    ({})
-#define dbg_dump_lpt_info(c)                  ({})
-#define dbg_dump_leb(c, lnum)                 ({})
-#define dbg_dump_znode(c, znode)              ({})
-#define dbg_dump_heap(c, heap, cat)           ({})
-#define dbg_dump_pnode(c, pnode, parent, iip) ({})
-#define dbg_dump_tnc(c)                       ({})
-#define dbg_dump_index(c)                     ({})
+#define ubifs_debugging_init(c)                0
+#define ubifs_debugging_exit(c)                ({})
+
+#define dbg_ntype(type)                        ""
+#define dbg_cstate(cmt_state)                  ""
+#define dbg_get_key_dump(c, key)               ({})
+#define dbg_dump_inode(c, inode)               ({})
+#define dbg_dump_node(c, node)                 ({})
+#define dbg_dump_lpt_node(c, node, lnum, offs) ({})
+#define dbg_dump_budget_req(req)               ({})
+#define dbg_dump_lstats(lst)                   ({})
+#define dbg_dump_budg(c)                       ({})
+#define dbg_dump_lprop(c, lp)                  ({})
+#define dbg_dump_lprops(c)                     ({})
+#define dbg_dump_lpt_info(c)                   ({})
+#define dbg_dump_leb(c, lnum)                  ({})
+#define dbg_dump_znode(c, znode)               ({})
+#define dbg_dump_heap(c, heap, cat)            ({})
+#define dbg_dump_pnode(c, pnode, parent, iip)  ({})
+#define dbg_dump_tnc(c)                        ({})
+#define dbg_dump_index(c)                      ({})
+#define dbg_dump_lpt_lebs(c)                   ({})
 
 #define dbg_walk_index(c, leaf_cb, znode_cb, priv) 0
 #define dbg_old_index_check_init(c, zroot)         0
diff --git a/fs/ubifs/lpt.c b/fs/ubifs/lpt.c
index 93c181c742f2..6d914160ec55 100644
--- a/fs/ubifs/lpt.c
+++ b/fs/ubifs/lpt.c
@@ -557,7 +557,7 @@ static int calc_nnode_num(int row, int col)
  * This function calculates and returns the nnode number based on the parent's
  * nnode number and the index in parent.
  */
-static int calc_nnode_num_from_parent(struct ubifs_info *c,
+static int calc_nnode_num_from_parent(const struct ubifs_info *c,
                                       struct ubifs_nnode *parent, int iip)
 {
         int num, shft;
@@ -582,7 +582,7 @@ static int calc_nnode_num_from_parent(struct ubifs_info *c,
  * This function calculates and returns the pnode number based on the parent's
  * nnode number and the index in parent.
  */
-static int calc_pnode_num_from_parent(struct ubifs_info *c,
+static int calc_pnode_num_from_parent(const struct ubifs_info *c,
                                       struct ubifs_nnode *parent, int iip)
 {
         int i, n = c->lpt_hght - 1, pnum = parent->num, num = 0;
@@ -965,7 +965,7 @@ static int check_lpt_type(uint8_t **addr, int *pos, int type)
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int unpack_pnode(struct ubifs_info *c, void *buf,
+static int unpack_pnode(const struct ubifs_info *c, void *buf,
                         struct ubifs_pnode *pnode)
 {
         uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
@@ -995,15 +995,15 @@ static int unpack_pnode(struct ubifs_info *c, void *buf,
 }
 
 /**
- * unpack_nnode - unpack a nnode.
+ * ubifs_unpack_nnode - unpack a nnode.
  * @c: UBIFS file-system description object
  * @buf: buffer containing packed nnode to unpack
  * @nnode: nnode structure to fill
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int unpack_nnode(struct ubifs_info *c, void *buf,
-                        struct ubifs_nnode *nnode)
+int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf,
+                       struct ubifs_nnode *nnode)
 {
         uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
         int i, pos = 0, err;
@@ -1035,7 +1035,7 @@ static int unpack_nnode(struct ubifs_info *c, void *buf,
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int unpack_ltab(struct ubifs_info *c, void *buf)
+static int unpack_ltab(const struct ubifs_info *c, void *buf)
 {
         uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
         int i, pos = 0, err;
@@ -1067,7 +1067,7 @@ static int unpack_ltab(struct ubifs_info *c, void *buf)
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int unpack_lsave(struct ubifs_info *c, void *buf)
+static int unpack_lsave(const struct ubifs_info *c, void *buf)
 {
         uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
         int i, pos = 0, err;
@@ -1095,7 +1095,7 @@ static int unpack_lsave(struct ubifs_info *c, void *buf)
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int validate_nnode(struct ubifs_info *c, struct ubifs_nnode *nnode,
+static int validate_nnode(const struct ubifs_info *c, struct ubifs_nnode *nnode,
                           struct ubifs_nnode *parent, int iip)
 {
         int i, lvl, max_offs;
@@ -1139,7 +1139,7 @@ static int validate_nnode(struct ubifs_info *c, struct ubifs_nnode *nnode,
  *
  * This function returns %0 on success and a negative error code on failure.
  */
-static int validate_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
+static int validate_pnode(const struct ubifs_info *c, struct ubifs_pnode *pnode,
                           struct ubifs_nnode *parent, int iip)
 {
         int i;
@@ -1173,7 +1173,8 @@ static int validate_pnode(struct ubifs_info *c, struct ubifs_pnode *pnode,
  * This function calculates the LEB numbers for the LEB properties it contains
  * based on the pnode number.
  */
-static void set_pnode_lnum(struct ubifs_info *c, struct ubifs_pnode *pnode)
+static void set_pnode_lnum(const struct ubifs_info *c,
+                           struct ubifs_pnode *pnode)
 {
         int i, lnum;
 
@@ -1226,7 +1227,7 @@ int ubifs_read_nnode(struct ubifs_info *c, struct ubifs_nnode *parent, int iip)
                 err = ubi_read(c->ubi, lnum, buf, offs, c->nnode_sz);
                 if (err)
                         goto out;
-                err = unpack_nnode(c, buf, nnode);
+                err = ubifs_unpack_nnode(c, buf, nnode);
                 if (err)
                         goto out;
         }
@@ -1815,7 +1816,7 @@ static struct ubifs_nnode *scan_get_nnode(struct ubifs_info *c,
                                c->nnode_sz);
                 if (err)
                         return ERR_PTR(err);
-                err = unpack_nnode(c, buf, nnode);
+                err = ubifs_unpack_nnode(c, buf, nnode);
                 if (err)
                         return ERR_PTR(err);
         }
diff --git a/fs/ubifs/lpt_commit.c b/fs/ubifs/lpt_commit.c
index c5c07f9cd22c..da60b5a0fab9 100644
--- a/fs/ubifs/lpt_commit.c
+++ b/fs/ubifs/lpt_commit.c
@@ -320,6 +320,7 @@ no_space:
         dbg_err("LPT out of space at LEB %d:%d needing %d, done_ltab %d, "
                 "done_lsave %d", lnum, offs, len, done_ltab, done_lsave);
         dbg_dump_lpt_info(c);
+        dbg_dump_lpt_lebs(c);
         dump_stack();
         return err;
 }
@@ -549,6 +550,7 @@ no_space:
         dbg_err("LPT out of space mismatch at LEB %d:%d needing %d, done_ltab "
                 "%d, done_lsave %d", lnum, offs, len, done_ltab, done_lsave);
         dbg_dump_lpt_info(c);
+        dbg_dump_lpt_lebs(c);
         dump_stack();
         return err;
 }
@@ -1027,7 +1029,7 @@ static int make_node_dirty(struct ubifs_info *c, int node_type, int node_num,
  * @c: UBIFS file-system description object
  * @node_type: LPT node type
  */
-static int get_lpt_node_len(struct ubifs_info *c, int node_type)
+static int get_lpt_node_len(const struct ubifs_info *c, int node_type)
 {
         switch (node_type) {
         case UBIFS_LPT_NNODE:
@@ -1048,7 +1050,7 @@ static int get_lpt_node_len(struct ubifs_info *c, int node_type)
  * @buf: buffer
  * @len: length of buffer
  */
-static int get_pad_len(struct ubifs_info *c, uint8_t *buf, int len)
+static int get_pad_len(const struct ubifs_info *c, uint8_t *buf, int len)
 {
         int offs, pad_len;
 
@@ -1065,7 +1067,8 @@ static int get_pad_len(struct ubifs_info *c, uint8_t *buf, int len)
  * @buf: buffer
  * @node_num: node number is returned here
  */
-static int get_lpt_node_type(struct ubifs_info *c, uint8_t *buf, int *node_num)
+static int get_lpt_node_type(const struct ubifs_info *c, uint8_t *buf,
+                             int *node_num)
 {
         uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
         int pos = 0, node_type;
@@ -1083,7 +1086,7 @@ static int get_lpt_node_type(struct ubifs_info *c, uint8_t *buf, int *node_num)
  *
  * This function returns %1 if the buffer contains a node or %0 if it does not.
  */
-static int is_a_node(struct ubifs_info *c, uint8_t *buf, int len)
+static int is_a_node(const struct ubifs_info *c, uint8_t *buf, int len)
 {
         uint8_t *addr = buf + UBIFS_LPT_CRC_BYTES;
         int pos = 0, node_type, node_len;
@@ -1107,7 +1110,6 @@ static int is_a_node(struct ubifs_info *c, uint8_t *buf, int len)
         return 1;
 }
 
-
 /**
  * lpt_gc_lnum - garbage collect a LPT LEB.
  * @c: UBIFS file-system description object
@@ -1724,6 +1726,7 @@ int dbg_chk_lpt_free_spc(struct ubifs_info *c)
                 dbg_err("LPT space error: free %lld lpt_sz %lld",
                         free, c->lpt_sz);
                 dbg_dump_lpt_info(c);
+                dbg_dump_lpt_lebs(c);
                 dump_stack();
                 return -EINVAL;
         }
@@ -1808,6 +1811,7 @@ int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
                 }
                 if (err) {
                         dbg_dump_lpt_info(c);
+                        dbg_dump_lpt_lebs(c);
                         dump_stack();
                 }
                 d->chk_lpt_sz2 = d->chk_lpt_sz;
@@ -1825,4 +1829,121 @@ int dbg_chk_lpt_sz(struct ubifs_info *c, int action, int len)
         }
 }
 
+/**
+ * dbg_dump_lpt_leb - dump an LPT LEB.
+ * @c: UBIFS file-system description object
+ * @lnum: LEB number to dump
+ *
+ * This function dumps an LEB from LPT area. Nodes in this area are very
+ * different to nodes in the main area (e.g., they do not have common headers,
+ * they do not have 8-byte alignments, etc), so we have a separate function to
+ * dump LPT area LEBs. Note, LPT has to be locked by the coller.
+ */
+static void dump_lpt_leb(const struct ubifs_info *c, int lnum)
+{
+        int err, len = c->leb_size, node_type, node_num, node_len, offs;
+        void *buf = c->dbg->buf;
+
+        printk(KERN_DEBUG "(pid %d) start dumping LEB %d\n",
+               current->pid, lnum);
+        err = ubi_read(c->ubi, lnum, buf, 0, c->leb_size);
+        if (err) {
+                ubifs_err("cannot read LEB %d, error %d", lnum, err);
+                return;
+        }
+        while (1) {
+                offs = c->leb_size - len;
+                if (!is_a_node(c, buf, len)) {
+                        int pad_len;
+
+                        pad_len = get_pad_len(c, buf, len);
+                        if (pad_len) {
+                                printk(KERN_DEBUG "LEB %d:%d, pad %d bytes\n",
+                                       lnum, offs, pad_len);
+                                buf += pad_len;
+                                len -= pad_len;
+                                continue;
+                        }
+                        if (len)
+                                printk(KERN_DEBUG "LEB %d:%d, free %d bytes\n",
+                                       lnum, offs, len);
+                        break;
+                }
+
+                node_type = get_lpt_node_type(c, buf, &node_num);
+                switch (node_type) {
+                case UBIFS_LPT_PNODE:
+                {
+                        node_len = c->pnode_sz;
+                        if (c->big_lpt)
+                                printk(KERN_DEBUG "LEB %d:%d, pnode num %d\n",
+                                       lnum, offs, node_num);
+                        else
+                                printk(KERN_DEBUG "LEB %d:%d, pnode\n",
+                                       lnum, offs);
+                        break;
+                }
+                case UBIFS_LPT_NNODE:
+                {
+                        int i;
+                        struct ubifs_nnode nnode;
+
+                        node_len = c->nnode_sz;
+                        if (c->big_lpt)
+                                printk(KERN_DEBUG "LEB %d:%d, nnode num %d, ",
+                                       lnum, offs, node_num);
+                        else
+                                printk(KERN_DEBUG "LEB %d:%d, nnode, ",
+                                       lnum, offs);
+                        err = ubifs_unpack_nnode(c, buf, &nnode);
+                        for (i = 0; i < UBIFS_LPT_FANOUT; i++) {
+                                printk("%d:%d", nnode.nbranch[i].lnum,
+                                       nnode.nbranch[i].offs);
+                                if (i != UBIFS_LPT_FANOUT - 1)
+                                        printk(", ");
+                        }
+                        printk("\n");
+                        break;
+                }
+                case UBIFS_LPT_LTAB:
+                        node_len = c->ltab_sz;
+                        printk(KERN_DEBUG "LEB %d:%d, ltab\n",
+                               lnum, offs);
+                        break;
+                case UBIFS_LPT_LSAVE:
+                        node_len = c->lsave_sz;
+                        printk(KERN_DEBUG "LEB %d:%d, lsave len\n", lnum, offs);
+                        break;
+                default:
+                        ubifs_err("LPT node type %d not recognized", node_type);
+                        return;
+                }
+
+                buf += node_len;
+                len -= node_len;
+        }
+
+        printk(KERN_DEBUG "(pid %d) finish dumping LEB %d\n",
+               current->pid, lnum);
+}
+
+/**
+ * dbg_dump_lpt_lebs - dump LPT lebs.
+ * @c: UBIFS file-system description object
+ *
+ * This function dumps all LPT LEBs. The caller has to make sure the LPT is
+ * locked.
+ */
+void dbg_dump_lpt_lebs(const struct ubifs_info *c)
+{
+        int i;
+
+        printk(KERN_DEBUG "(pid %d) start dumping all LPT LEBs\n",
+               current->pid);
+        for (i = 0; i < c->lpt_lebs; i++)
+                dump_lpt_leb(c, i + c->lpt_first);
+        printk(KERN_DEBUG "(pid %d) finish dumping all LPT LEBs\n",
+               current->pid);
+}
+
 #endif /* CONFIG_UBIFS_FS_DEBUG */
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index 4cf28e85de78..e658b06fd451 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1622,6 +1622,9 @@ void ubifs_add_lpt_dirt(struct ubifs_info *c, int lnum, int dirty);
 void ubifs_add_nnode_dirt(struct ubifs_info *c, struct ubifs_nnode *nnode);
 uint32_t ubifs_unpack_bits(uint8_t **addr, int *pos, int nrbits);
 struct ubifs_nnode *ubifs_first_nnode(struct ubifs_info *c, int *hght);
+/* Needed only in debugging code in lpt_commit.c */
+int ubifs_unpack_nnode(const struct ubifs_info *c, void *buf,
+                       struct ubifs_nnode *nnode);
 
 /* lpt_commit.c */
 int ubifs_lpt_start_commit(struct ubifs_info *c);