UBI: prepare debugging stuff to further debugfs conversion

We'll need the 'struct ubi_device *ubi' pointer in every debugging function (to
access the ->dbg field), so add this pointer to all the functions implementing
UBI debugging test modes like 'ubi_dbg_is_bitflip()' etc.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/debug.h b/drivers/mtd/ubi/debug.h
index cb6c879..efefc54 100644
--- a/drivers/mtd/ubi/debug.h
+++ b/drivers/mtd/ubi/debug.h
@@ -126,21 +126,23 @@
 
 /**
  * ubi_dbg_is_bgt_disabled - if the background thread is disabled.
+ * @ubi: UBI device description object
  *
  * Returns non-zero if the UBI background thread is disabled for testing
  * purposes.
  */
-static inline int ubi_dbg_is_bgt_disabled(void)
+static inline int ubi_dbg_is_bgt_disabled(const struct ubi_device *ubi)
 {
 	return ubi_tst_flags & UBI_TST_DISABLE_BGT;
 }
 
 /**
  * ubi_dbg_is_bitflip - if it is time to emulate a bit-flip.
+ * @ubi: UBI device description object
  *
  * Returns non-zero if a bit-flip should be emulated, otherwise returns zero.
  */
-static inline int ubi_dbg_is_bitflip(void)
+static inline int ubi_dbg_is_bitflip(const struct ubi_device *ubi)
 {
 	if (ubi_tst_flags & UBI_TST_EMULATE_BITFLIPS)
 		return !(random32() % 200);
@@ -149,11 +151,12 @@
 
 /**
  * ubi_dbg_is_write_failure - if it is time to emulate a write failure.
+ * @ubi: UBI device description object
  *
  * Returns non-zero if a write failure should be emulated, otherwise returns
  * zero.
  */
-static inline int ubi_dbg_is_write_failure(void)
+static inline int ubi_dbg_is_write_failure(const struct ubi_device *ubi)
 {
 	if (ubi_tst_flags & UBI_TST_EMULATE_WRITE_FAILURES)
 		return !(random32() % 500);
@@ -162,11 +165,12 @@
 
 /**
  * ubi_dbg_is_erase_failure - if its time to emulate an erase failure.
+ * @ubi: UBI device description object
  *
  * Returns non-zero if an erase failure should be emulated, otherwise returns
  * zero.
  */
-static inline int ubi_dbg_is_erase_failure(void)
+static inline int ubi_dbg_is_erase_failure(const struct ubi_device *ubi)
 {
 	if (ubi_tst_flags & UBI_TST_EMULATE_ERASE_FAILURES)
 		return !(random32() % 400);
@@ -233,10 +237,13 @@
 static inline int ubi_debugfs_init_dev(struct ubi_device *ubi)     { return 0; }
 static inline void ubi_debugfs_exit_dev(struct ubi_device *ubi)    { return; }
 
-static inline int ubi_dbg_is_bgt_disabled(void)                    { return 0; }
-static inline int ubi_dbg_is_bitflip(void)                         { return 0; }
-static inline int ubi_dbg_is_write_failure(void)                   { return 0; }
-static inline int ubi_dbg_is_erase_failure(void)                   { return 0; }
+static inline int
+ubi_dbg_is_bgt_disabled(const struct ubi_device *ubi)              { return 0; }
+static inline int ubi_dbg_is_bitflip(const struct ubi_device *ubi) { return 0; }
+static inline int
+ubi_dbg_is_write_failure(const struct ubi_device *ubi)             { return 0; }
+static inline int
+ubi_dbg_is_erase_failure(const struct ubi_device *ubi)             { return 0; }
 
 #endif /* !CONFIG_MTD_UBI_DEBUG */
 #endif /* !__UBI_DEBUG_H__ */
diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c
index e23d611..6ba55c2 100644
--- a/drivers/mtd/ubi/io.c
+++ b/drivers/mtd/ubi/io.c
@@ -212,7 +212,7 @@
 	} else {
 		ubi_assert(len == read);
 
-		if (ubi_dbg_is_bitflip()) {
+		if (ubi_dbg_is_bitflip(ubi)) {
 			dbg_gen("bit-flip (emulated)");
 			err = UBI_IO_BITFLIPS;
 		}
@@ -281,7 +281,7 @@
 			return err;
 	}
 
-	if (ubi_dbg_is_write_failure()) {
+	if (ubi_dbg_is_write_failure(ubi)) {
 		dbg_err("cannot write %d bytes to PEB %d:%d "
 			"(emulated)", len, pnum, offset);
 		ubi_dbg_dump_stack();
@@ -396,7 +396,7 @@
 	if (err)
 		return err;
 
-	if (ubi_dbg_is_erase_failure()) {
+	if (ubi_dbg_is_erase_failure(ubi)) {
 		dbg_err("cannot erase PEB %d (emulated)", pnum);
 		return -EIO;
 	}
diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index bf13ca2..42c684c 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -616,7 +616,7 @@
 	list_add_tail(&wrk->list, &ubi->works);
 	ubi_assert(ubi->works_count >= 0);
 	ubi->works_count += 1;
-	if (ubi->thread_enabled && !ubi_dbg_is_bgt_disabled())
+	if (ubi->thread_enabled && !ubi_dbg_is_bgt_disabled(ubi))
 		wake_up_process(ubi->bgt_thread);
 	spin_unlock(&ubi->wl_lock);
 }
@@ -1367,7 +1367,7 @@
 
 		spin_lock(&ubi->wl_lock);
 		if (list_empty(&ubi->works) || ubi->ro_mode ||
-		    !ubi->thread_enabled || ubi_dbg_is_bgt_disabled()) {
+		    !ubi->thread_enabled || ubi_dbg_is_bgt_disabled(ubi)) {
 			set_current_state(TASK_INTERRUPTIBLE);
 			spin_unlock(&ubi->wl_lock);
 			schedule();