Merge branch 'linux-next' of git://git.infradead.org/ubi-2.6

* 'linux-next' of git://git.infradead.org/ubi-2.6:
  UBI: make tests modes dynamic
  UBI: make self-checks dynamic
  UBI: make debugging messages dynamic
  UBI: remove UBI_IO_DEBUG macro
  UBI: kill debugging buffer
  UBI: allocate erase checking buffer on demand
  UBI: allocate write checking buffer on demand
  UBI: always re-read in case of read failures
  UBI: cleanup comments about corrupted PEBs
  UBI: add slab cache for ubi_scan_leb objects
  UBI: use raw mtd read function in debugging code
  UBI: try to reveal buggy MTD drivers
  UBI: add a commentary about allocating VID header buffer on stack
  UBI: cleanup LEB start calculations
  UBI: fix NOR erase preparation quirk

drivers/mtd/ubi/Kconfig

@@ -52,6 +52,12 @@ config MTD_UBI_GLUEBI
 	   work on top of UBI. Do not enable this unless you use legacy
 	   software.
 
-source "drivers/mtd/ubi/Kconfig.debug"
+config MTD_UBI_DEBUG
+	bool "UBI debugging"
+	depends on SYSFS
+	select DEBUG_FS
+	select KALLSYMS_ALL if KALLSYMS && DEBUG_KERNEL
+	help
+	  This option enables UBI debugging.
 
 endif # MTD_UBI

drivers/mtd/ubi/build.c

@@ -711,7 +711,7 @@ static int io_init(struct ubi_device *ubi)
 	}
 
 	/* Similar for the data offset */
-	ubi->leb_start = ubi->vid_hdr_offset + UBI_EC_HDR_SIZE;
+	ubi->leb_start = ubi->vid_hdr_offset + UBI_VID_HDR_SIZE;
 	ubi->leb_start = ALIGN(ubi->leb_start, ubi->min_io_size);
 
 	dbg_msg("vid_hdr_offset   %d", ubi->vid_hdr_offset);
@@ -923,6 +923,8 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
 	spin_lock_init(&ubi->volumes_lock);
 
 	ubi_msg("attaching mtd%d to ubi%d", mtd->index, ubi_num);
+	dbg_msg("sizeof(struct ubi_scan_leb) %zu", sizeof(struct ubi_scan_leb));
+	dbg_msg("sizeof(struct ubi_wl_entry) %zu", sizeof(struct ubi_wl_entry));
 
 	err = io_init(ubi);
 	if (err)
@@ -937,13 +939,6 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
 	if (!ubi->peb_buf2)
 		goto out_free;
 
-#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
-	mutex_init(&ubi->dbg_buf_mutex);
-	ubi->dbg_peb_buf = vmalloc(ubi->peb_size);
-	if (!ubi->dbg_peb_buf)
-		goto out_free;
-#endif
-
 	err = attach_by_scanning(ubi);
 	if (err) {
 		dbg_err("failed to attach by scanning, error %d", err);
@@ -991,8 +986,7 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
 	 * checks @ubi->thread_enabled. Otherwise we may fail to wake it up.
 	 */
 	spin_lock(&ubi->wl_lock);
-	if (!DBG_DISABLE_BGT)
-		ubi->thread_enabled = 1;
+	ubi->thread_enabled = 1;
 	wake_up_process(ubi->bgt_thread);
 	spin_unlock(&ubi->wl_lock);
 
@@ -1009,9 +1003,6 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
 out_free:
 	vfree(ubi->peb_buf1);
 	vfree(ubi->peb_buf2);
-#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
-	vfree(ubi->dbg_peb_buf);
-#endif
 	if (ref)
 		put_device(&ubi->dev);
 	else
@@ -1082,9 +1073,6 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
 	put_mtd_device(ubi->mtd);
 	vfree(ubi->peb_buf1);
 	vfree(ubi->peb_buf2);
-#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
-	vfree(ubi->dbg_peb_buf);
-#endif
 	ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num);
 	put_device(&ubi->dev);
 	return 0;

drivers/mtd/ubi/debug.c

@@ -27,6 +27,20 @@
 #ifdef CONFIG_MTD_UBI_DEBUG
 
 #include "ubi.h"
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+
+unsigned int ubi_msg_flags;
+unsigned int ubi_chk_flags;
+unsigned int ubi_tst_flags;
+
+module_param_named(debug_msgs, ubi_msg_flags, uint, S_IRUGO | S_IWUSR);
+module_param_named(debug_chks, ubi_chk_flags, uint, S_IRUGO | S_IWUSR);
+module_param_named(debug_tsts, ubi_chk_flags, uint, S_IRUGO | S_IWUSR);
+
+MODULE_PARM_DESC(debug_msgs, "Debug message type flags");
+MODULE_PARM_DESC(debug_chks, "Debug check flags");
+MODULE_PARM_DESC(debug_tsts, "Debug special test flags");
 
 /**
  * ubi_dbg_dump_ec_hdr - dump an erase counter header.

drivers/mtd/ubi/debug.h

@@ -38,6 +38,11 @@
 	printk(KERN_DEBUG "UBI DBG (pid %d): %s: " fmt "\n", \
 	       current->pid, __func__, ##__VA_ARGS__)
 
+#define dbg_do_msg(typ, fmt, ...) do {                       \
+	if (ubi_msg_flags & typ)                             \
+		dbg_msg(fmt, ##__VA_ARGS__);                 \
+} while (0)
+
 #define ubi_dbg_dump_stack() dump_stack()
 
 struct ubi_ec_hdr;
@@ -57,76 +62,100 @@ void ubi_dbg_dump_seb(const struct ubi_scan_leb *seb, int type);
 void ubi_dbg_dump_mkvol_req(const struct ubi_mkvol_req *req);
 void ubi_dbg_dump_flash(struct ubi_device *ubi, int pnum, int offset, int len);
 
+extern unsigned int ubi_msg_flags;
+
+/*
+ * Debugging message type flags (must match msg_type_names in debug.c).
+ *
+ * UBI_MSG_GEN: general messages
+ * UBI_MSG_EBA: journal messages
+ * UBI_MSG_WL: mount messages
+ * UBI_MSG_IO: commit messages
+ * UBI_MSG_BLD: LEB find messages
+ */
+enum {
+	UBI_MSG_GEN  = 0x1,
+	UBI_MSG_EBA  = 0x2,
+	UBI_MSG_WL   = 0x4,
+	UBI_MSG_IO   = 0x8,
+	UBI_MSG_BLD  = 0x10,
+};
+
 #define ubi_dbg_print_hex_dump(l, ps, pt, r, g, b, len, a)  \
 		print_hex_dump(l, ps, pt, r, g, b, len, a)
 
-#ifdef CONFIG_MTD_UBI_DEBUG_MSG
 /* General debugging messages */
-#define dbg_gen(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__)
-#else
-#define dbg_gen(fmt, ...) ({})
-#endif
+#define dbg_gen(fmt, ...) dbg_do_msg(UBI_MSG_GEN, fmt, ##__VA_ARGS__)
 
-#ifdef CONFIG_MTD_UBI_DEBUG_MSG_EBA
 /* Messages from the eraseblock association sub-system */
-#define dbg_eba(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__)
-#else
-#define dbg_eba(fmt, ...) ({})
-#endif
+#define dbg_eba(fmt, ...) dbg_do_msg(UBI_MSG_EBA, fmt, ##__VA_ARGS__)
 
-#ifdef CONFIG_MTD_UBI_DEBUG_MSG_WL
 /* Messages from the wear-leveling sub-system */
-#define dbg_wl(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__)
-#else
-#define dbg_wl(fmt, ...) ({})
-#endif
+#define dbg_wl(fmt, ...) dbg_do_msg(UBI_MSG_WL, fmt, ##__VA_ARGS__)
 
-#ifdef CONFIG_MTD_UBI_DEBUG_MSG_IO
 /* Messages from the input/output sub-system */
-#define dbg_io(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__)
-#else
-#define dbg_io(fmt, ...) ({})
-#endif
+#define dbg_io(fmt, ...) dbg_do_msg(UBI_MSG_IO, fmt, ##__VA_ARGS__)
 
-#ifdef CONFIG_MTD_UBI_DEBUG_MSG_BLD
 /* Initialization and build messages */
-#define dbg_bld(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__)
-#define UBI_IO_DEBUG 1
-#else
-#define dbg_bld(fmt, ...) ({})
-#define UBI_IO_DEBUG 0
-#endif
+#define dbg_bld(fmt, ...) dbg_do_msg(UBI_MSG_BLD, fmt, ##__VA_ARGS__)
+
+extern unsigned int ubi_chk_flags;
+
+/*
+ * Debugging check flags.
+ *
+ * UBI_CHK_GEN: general checks
+ * UBI_CHK_IO: check writes and erases
+ */
+enum {
+	UBI_CHK_GEN = 0x1,
+	UBI_CHK_IO  = 0x2,
+};
 
-#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
 int ubi_dbg_check_all_ff(struct ubi_device *ubi, int pnum, int offset, int len);
 int ubi_dbg_check_write(struct ubi_device *ubi, const void *buf, int pnum,
 			int offset, int len);
-#else
-#define ubi_dbg_check_all_ff(ubi, pnum, offset, len) 0
-#define ubi_dbg_check_write(ubi, buf, pnum, offset, len) 0
-#endif
 
-#ifdef CONFIG_MTD_UBI_DEBUG_DISABLE_BGT
-#define DBG_DISABLE_BGT 1
-#else
-#define DBG_DISABLE_BGT 0
-#endif
+extern unsigned int ubi_tst_flags;
+
+/*
+ * Special testing flags.
+ *
+ * UBIFS_TST_DISABLE_BGT: disable the background thread
+ * UBI_TST_EMULATE_BITFLIPS: emulate bit-flips
+ * UBI_TST_EMULATE_WRITE_FAILURES: emulate write failures
+ * UBI_TST_EMULATE_ERASE_FAILURES: emulate erase failures
+ */
+enum {
+	UBI_TST_DISABLE_BGT            = 0x1,
+	UBI_TST_EMULATE_BITFLIPS       = 0x2,
+	UBI_TST_EMULATE_WRITE_FAILURES = 0x4,
+	UBI_TST_EMULATE_ERASE_FAILURES = 0x8,
+};
+
+/**
+ * ubi_dbg_is_bgt_disabled - if the background thread is disabled.
+ *
+ * Returns non-zero if the UBI background thread is disabled for testing
+ * purposes.
+ */
+static inline int ubi_dbg_is_bgt_disabled(void)
+{
+	return ubi_tst_flags & UBI_TST_DISABLE_BGT;
+}
 
-#ifdef CONFIG_MTD_UBI_DEBUG_EMULATE_BITFLIPS
 /**
  * ubi_dbg_is_bitflip - if it is time to emulate a bit-flip.
  *
  * Returns non-zero if a bit-flip should be emulated, otherwise returns zero.
  */
 static inline int ubi_dbg_is_bitflip(void)
 {
-	return !(random32() % 200);
+	if (ubi_tst_flags & UBI_TST_EMULATE_BITFLIPS)
+		return !(random32() % 200);
+	return 0;
 }
-#else
-#define ubi_dbg_is_bitflip() 0
-#endif
 
-#ifdef CONFIG_MTD_UBI_DEBUG_EMULATE_WRITE_FAILURES
 /**
  * ubi_dbg_is_write_failure - if it is time to emulate a write failure.
  *
@@ -135,13 +164,11 @@ static inline int ubi_dbg_is_bitflip(void)
  */
 static inline int ubi_dbg_is_write_failure(void)
 {
-	return !(random32() % 500);
+	if (ubi_tst_flags & UBI_TST_EMULATE_WRITE_FAILURES)
+		return !(random32() % 500);
+	return 0;
 }
-#else
-#define ubi_dbg_is_write_failure() 0
-#endif
 
-#ifdef CONFIG_MTD_UBI_DEBUG_EMULATE_ERASE_FAILURES
 /**
  * ubi_dbg_is_erase_failure - if its time to emulate an erase failure.
  *
@@ -150,11 +177,10 @@ static inline int ubi_dbg_is_write_failure(void)
  */
 static inline int ubi_dbg_is_erase_failure(void)
 {
+	if (ubi_tst_flags & UBI_TST_EMULATE_ERASE_FAILURES)
 		return !(random32() % 400);
+	return 0;
 }
-#else
-#define ubi_dbg_is_erase_failure() 0
-#endif
 
 #else
 
@@ -177,8 +203,7 @@ static inline int ubi_dbg_is_erase_failure(void)
 #define ubi_dbg_dump_flash(ubi, pnum, offset, len) ({})
 #define ubi_dbg_print_hex_dump(l, ps, pt, r, g, b, len, a)  ({})
 
-#define UBI_IO_DEBUG               0
-#define DBG_DISABLE_BGT            0
+#define ubi_dbg_is_bgt_disabled()  0
 #define ubi_dbg_is_bitflip()       0
 #define ubi_dbg_is_write_failure() 0
 #define ubi_dbg_is_erase_failure() 0