Merge git://git.infradead.org/~dedekind/ubi-2.6

11 files changed, 260 insertions, 64 deletions

diff --git a/Documentation/ABI/stable/sysfs-class-ubi b/Documentation/ABI/stable/sysfs-class-ubi
new file mode 100644
index 00000000000..18d471d9fae
--- /dev/null
+++ b/Documentation/ABI/stable/sysfs-class-ubi
@@ -0,0 +1,212 @@
+What:		/sys/class/ubi/
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		The ubi/ class sub-directory belongs to the UBI subsystem and
+		provides general UBI information, per-UBI device information
+		and per-UBI volume information.
+
+What:		/sys/class/ubi/version
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		This file contains version of the latest supported UBI on-media
+		format. Currently it is 1, and there is no plan to change this.
+		However, if in the future UBI needs on-flash format changes
+		which cannot be done in a compatible manner, a new format
+		version will be added. So this is a mechanism for possible
+		future backward-compatible (but forward-incompatible)
+		improvements.
+
+What:		/sys/class/ubiX/
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		The /sys/class/ubi0, /sys/class/ubi1, etc directories describe
+		UBI devices (UBI device 0, 1, etc). They contain general UBI
+		device information and per UBI volume information (each UBI
+		device may have many UBI volumes)
+
+What:		/sys/class/ubi/ubiX/avail_eraseblocks
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Amount of available logical eraseblock. For example, one may
+		create a new UBI volume which has this amount of logical
+		eraseblocks.
+
+What:		/sys/class/ubi/ubiX/bad_peb_count
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Count of bad physical eraseblocks on the underlying MTD device.
+
+What:		/sys/class/ubi/ubiX/bgt_enabled
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Contains ASCII "0\n" if the UBI background thread is disabled,
+		and ASCII "1\n" if it is enabled.
+
+What:		/sys/class/ubi/ubiX/dev
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Major and minor numbers of the character device corresponding
+		to this UBI device (in <major>:<minor> format).
+
+What:		/sys/class/ubi/ubiX/eraseblock_size
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Maximum logical eraseblock size this UBI device may provide. UBI
+		volumes may have smaller logical eraseblock size because of their
+		alignment.
+
+What:		/sys/class/ubi/ubiX/max_ec
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Maximum physical eraseblock erase counter value.
+
+What:		/sys/class/ubi/ubiX/max_vol_count
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Maximum number of volumes which this UBI device may have.
+
+What:		/sys/class/ubi/ubiX/min_io_size
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Minimum input/output unit size. All the I/O may only be done
+		in fractions of the contained number.
+
+What:		/sys/class/ubi/ubiX/mtd_num
+Date:		January 2008
+KernelVersion:	2.6.25
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Number of the underlying MTD device.
+
+What:		/sys/class/ubi/ubiX/reserved_for_bad
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Number of physical eraseblocks reserved for bad block handling.
+
+What:		/sys/class/ubi/ubiX/total_eraseblocks
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Total number of good (not marked as bad) physical eraseblocks on
+		the underlying MTD device.
+
+What:		/sys/class/ubi/ubiX/volumes_count
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Count of volumes on this UBI device.
+
+What:		/sys/class/ubi/ubiX/ubiX_Y/
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		The /sys/class/ubi/ubiX/ubiX_0/, /sys/class/ubi/ubiX/ubiX_1/,
+		etc directories describe UBI volumes on UBI device X (volumes
+		0, 1, etc).
+
+What:		/sys/class/ubi/ubiX/ubiX_Y/alignment
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Volume alignment - the value the logical eraseblock size of
+		this volume has to be aligned on. For example, 2048 means that
+		logical eraseblock size is multiple of 2048. In other words,
+		volume logical eraseblock size is UBI device logical eraseblock
+		size aligned to the alignment value.
+
+What:		/sys/class/ubi/ubiX/ubiX_Y/corrupted
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Contains ASCII "0\n" if the UBI volume is OK, and ASCII "1\n"
+		if it is corrupted (e.g., due to an interrupted volume update).
+
+What:		/sys/class/ubi/ubiX/ubiX_Y/data_bytes
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		The amount of data this volume contains. This value makes sense
+		only for static volumes, and for dynamic volume it equivalent
+		to the total volume size in bytes.
+
+What:		/sys/class/ubi/ubiX/ubiX_Y/dev
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Major and minor numbers of the character device corresponding
+		to this UBI volume (in <major>:<minor> format).
+
+What:		/sys/class/ubi/ubiX/ubiX_Y/name
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Volume name.
+
+What:		/sys/class/ubi/ubiX/ubiX_Y/reserved_ebs
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Count of physical eraseblock reserved for this volume.
+		Equivalent to the volume size in logical eraseblocks.
+
+What:		/sys/class/ubi/ubiX/ubiX_Y/type
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Volume type. Contains ASCII "dynamic\n" for dynamic volumes and
+		"static\n" for static volumes.
+
+What:		/sys/class/ubi/ubiX/ubiX_Y/upd_marker
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Contains ASCII "0\n" if the update marker is not set for this
+		volume, and "1\n" if it is set. The update marker is set when
+		volume update starts, and cleaned when it ends. So the presence
+		of the update marker indicates that the volume is being updated
+		at the moment of the update was interrupted. The later may be
+		checked using the "corrupted" sysfs file.
+
+What:		/sys/class/ubi/ubiX/ubiX_Y/usable_eb_size
+Date:		July 2006
+KernelVersion:	2.6.22
+Contact:	Artem Bityutskiy <dedekind@infradead.org>
+Description:
+		Logical eraseblock size of this volume. Equivalent to logical
+		eraseblock size of the device aligned on the volume alignment
+		value.
diff --git a/drivers/mtd/ubi/Kconfig b/drivers/mtd/ubi/Kconfig
index b9daf159a4a..3f063108e95 100644
--- a/drivers/mtd/ubi/Kconfig
+++ b/drivers/mtd/ubi/Kconfig
@@ -24,8 +24,13 @@ config MTD_UBI_WL_THRESHOLD
 	  erase counter value and the lowest erase counter value of eraseblocks
 	  of UBI devices. When this threshold is exceeded, UBI starts performing
 	  wear leveling by means of moving data from eraseblock with low erase
-	  counter to eraseblocks with high erase counter. Leave the default
-	  value if unsure.
+	  counter to eraseblocks with high erase counter.
+
+	  The default value should be OK for SLC NAND flashes, NOR flashes and
+	  other flashes which have eraseblock life-cycle 100000 or more.
+	  However, in case of MLC NAND flashes which typically have eraseblock
+	  life-cycle less then 10000, the threshold should be lessened (e.g.,
+	  to 128 or 256, although it does not have to be power of 2).
 
 config MTD_UBI_BEB_RESERVE
 	int "Percentage of reserved eraseblocks for bad eraseblocks handling"
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 27596046297..e8578ca422f 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -606,8 +606,16 @@ static int io_init(struct ubi_device *ubi)
 		ubi->ro_mode = 1;
 	}
 
-	dbg_msg("leb_size         %d", ubi->leb_size);
-	dbg_msg("ro_mode          %d", ubi->ro_mode);
+	ubi_msg("physical eraseblock size:   %d bytes (%d KiB)",
+		ubi->peb_size, ubi->peb_size >> 10);
+	ubi_msg("logical eraseblock size:    %d bytes", ubi->leb_size);
+	ubi_msg("smallest flash I/O unit:    %d", ubi->min_io_size);
+	if (ubi->hdrs_min_io_size != ubi->min_io_size)
+		ubi_msg("sub-page size:              %d",
+			ubi->hdrs_min_io_size);
+	ubi_msg("VID header offset:          %d (aligned %d)",
+		ubi->vid_hdr_offset, ubi->vid_hdr_aloffset);
+	ubi_msg("data offset:                %d", ubi->leb_start);
 
 	/*
 	 * Note, ideally, we have to initialize ubi->bad_peb_count here. But
@@ -804,15 +812,8 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
 	ubi_msg("attached mtd%d to ubi%d", mtd->index, ubi_num);
 	ubi_msg("MTD device name:            \"%s\"", mtd->name);
 	ubi_msg("MTD device size:            %llu MiB", ubi->flash_size >> 20);
-	ubi_msg("physical eraseblock size:   %d bytes (%d KiB)",
-		ubi->peb_size, ubi->peb_size >> 10);
-	ubi_msg("logical eraseblock size:    %d bytes", ubi->leb_size);
 	ubi_msg("number of good PEBs:        %d", ubi->good_peb_count);
 	ubi_msg("number of bad PEBs:         %d", ubi->bad_peb_count);
-	ubi_msg("smallest flash I/O unit:    %d", ubi->min_io_size);
-	ubi_msg("VID header offset:          %d (aligned %d)",
-		ubi->vid_hdr_offset, ubi->vid_hdr_aloffset);
-	ubi_msg("data offset:                %d", ubi->leb_start);
 	ubi_msg("max. allowed volumes:       %d", ubi->vtbl_slots);
 	ubi_msg("wear-leveling threshold:    %d", CONFIG_MTD_UBI_WL_THRESHOLD);
 	ubi_msg("number of internal volumes: %d", UBI_INT_VOL_COUNT);
@@ -950,8 +951,7 @@ static int __init ubi_init(void)
 	BUILD_BUG_ON(sizeof(struct ubi_vid_hdr) != 64);
 
 	if (mtd_devs > UBI_MAX_DEVICES) {
-		printk(KERN_ERR "UBI error: too many MTD devices, "
-		       "maximum is %d\n", UBI_MAX_DEVICES);
+		ubi_err("too many MTD devices, maximum is %d", UBI_MAX_DEVICES);
 		return -EINVAL;
 	}
 
@@ -959,25 +959,25 @@ static int __init ubi_init(void)
 	ubi_class = class_create(THIS_MODULE, UBI_NAME_STR);
 	if (IS_ERR(ubi_class)) {
 		err = PTR_ERR(ubi_class);
-		printk(KERN_ERR "UBI error: cannot create UBI class\n");
+		ubi_err("cannot create UBI class");
 		goto out;
 	}
 
 	err = class_create_file(ubi_class, &ubi_version);
 	if (err) {
-		printk(KERN_ERR "UBI error: cannot create sysfs file\n");
+		ubi_err("cannot create sysfs file");
 		goto out_class;
 	}
 
 	err = misc_register(&ubi_ctrl_cdev);
 	if (err) {
-		printk(KERN_ERR "UBI error: cannot register device\n");
+		ubi_err("cannot register device");
 		goto out_version;
 	}
 
 	ubi_wl_entry_slab = kmem_cache_create("ubi_wl_entry_slab",
-						sizeof(struct ubi_wl_entry),
-						0, 0, NULL);
+					      sizeof(struct ubi_wl_entry),
+					      0, 0, NULL);
 	if (!ubi_wl_entry_slab)
 		goto out_dev_unreg;
 
@@ -1000,8 +1000,7 @@ static int __init ubi_init(void)
 		mutex_unlock(&ubi_devices_mutex);
 		if (err < 0) {
 			put_mtd_device(mtd);
-			printk(KERN_ERR "UBI error: cannot attach mtd%d\n",
-			       mtd->index);
+			ubi_err("cannot attach mtd%d", mtd->index);
 			goto out_detach;
 		}
 	}
@@ -1023,7 +1022,7 @@ out_version:
 out_class:
 	class_destroy(ubi_class);
 out:
-	printk(KERN_ERR "UBI error: cannot initialize UBI, error %d\n", err);
+	ubi_err("UBI error: cannot initialize UBI, error %d", err);
 	return err;
 }
 module_init(ubi_init);
diff --git a/drivers/mtd/ubi/debug.h b/drivers/mtd/ubi/debug.h
index 8ac7d87dc85..8ea99d8c9e1 100644
--- a/drivers/mtd/ubi/debug.h
+++ b/drivers/mtd/ubi/debug.h
@@ -99,8 +99,10 @@ void ubi_dbg_dump_mkvol_req(const struct ubi_mkvol_req *req);
 #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
 
 #ifdef CONFIG_MTD_UBI_DEBUG_EMULATE_BITFLIPS
diff --git a/drivers/mtd/ubi/gluebi.c b/drivers/mtd/ubi/gluebi.c
index d397219238d..e909b390069 100644
--- a/drivers/mtd/ubi/gluebi.c
+++ b/drivers/mtd/ubi/gluebi.c
@@ -291,11 +291,12 @@ int ubi_create_gluebi(struct ubi_device *ubi, struct ubi_volume *vol)
 	/*
 	 * In case of dynamic volume, MTD device size is just volume size. In
 	 * case of a static volume the size is equivalent to the amount of data
-	 * bytes, which is zero at this moment and will be changed after volume
-	 * update.
+	 * bytes.
 	 */
 	if (vol->vol_type == UBI_DYNAMIC_VOLUME)
 		mtd->size = vol->usable_leb_size * vol->reserved_pebs;
+	else
+		mtd->size = vol->used_bytes;
 
 	if (add_mtd_device(mtd)) {
 		ubi_err("cannot not add MTD device\n");
diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c
index db3efdef243..4ac11df7b04 100644
--- a/drivers/mtd/ubi/io.c
+++ b/drivers/mtd/ubi/io.c
@@ -631,6 +631,8 @@ int ubi_io_read_ec_hdr(struct ubi_device *ubi, int pnum,
 
 	dbg_io("read EC header from PEB %d", pnum);
 	ubi_assert(pnum >= 0 && pnum < ubi->peb_count);
+	if (UBI_IO_DEBUG)
+		verbose = 1;
 
 	err = ubi_io_read(ubi, ec_hdr, pnum, 0, UBI_EC_HDR_SIZE);
 	if (err) {
@@ -904,6 +906,8 @@ int ubi_io_read_vid_hdr(struct ubi_device *ubi, int pnum,
 
 	dbg_io("read VID header from PEB %d", pnum);
 	ubi_assert(pnum >= 0 &&  pnum < ubi->peb_count);
+	if (UBI_IO_DEBUG)
+		verbose = 1;
 
 	p = (char *)vid_hdr - ubi->vid_hdr_shift;
 	err = ubi_io_read(ubi, p, pnum, ubi->vid_hdr_aloffset,
diff --git a/drivers/mtd/ubi/scan.c b/drivers/mtd/ubi/scan.c
index 05aa3e7daba..96d410e106a 100644
--- a/drivers/mtd/ubi/scan.c
+++ b/drivers/mtd/ubi/scan.c
@@ -42,6 +42,7 @@
 
 #include <linux/err.h>
 #include <linux/crc32.h>
+#include <asm/div64.h>
 #include "ubi.h"
 
 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
@@ -92,27 +93,6 @@ static int add_to_list(struct ubi_scan_info *si, int pnum, int ec,
 }
 
 /**
- * commit_to_mean_value - commit intermediate results to the final mean erase
- * counter value.
- * @si: scanning information
- *
- * This is a helper function which calculates partial mean erase counter mean
- * value and adds it to the resulting mean value. As we can work only in
- * integer arithmetic and we want to calculate the mean value of erase counter
- * accurately, we first sum erase counter values in @si->ec_sum variable and
- * count these components in @si->ec_count. If this temporary @si->ec_sum is
- * going to overflow, we calculate the partial mean value
- * (@si->ec_sum/@si->ec_count) and add it to @si->mean_ec.
- */
-static void commit_to_mean_value(struct ubi_scan_info *si)
-{
-	si->ec_sum /= si->ec_count;
-	if (si->ec_sum % si->ec_count >= si->ec_count / 2)
-		si->mean_ec += 1;
-	si->mean_ec += si->ec_sum;
-}
-
-/**
  * validate_vid_hdr - check that volume identifier header is correct and
  * consistent.
  * @vid_hdr: the volume identifier header to check
@@ -901,15 +881,8 @@ static int process_eb(struct ubi_device *ubi, struct ubi_scan_info *si, int pnum
 
 adjust_mean_ec:
 	if (!ec_corr) {
-		if (si->ec_sum + ec < ec) {
-			commit_to_mean_value(si);
-			si->ec_sum = 0;
-			si->ec_count = 0;
-		} else {
-			si->ec_sum += ec;
-			si->ec_count += 1;
-		}
-
+		si->ec_sum += ec;
+		si->ec_count += 1;
 		if (ec > si->max_ec)
 			si->max_ec = ec;
 		if (ec < si->min_ec)
@@ -965,9 +938,11 @@ struct ubi_scan_info *ubi_scan(struct ubi_device *ubi)
 
 	dbg_msg("scanning is finished");
 
-	/* Finish mean erase counter calculations */
-	if (si->ec_count)
-		commit_to_mean_value(si);
+	/* Calculate mean erase counter */
+	if (si->ec_count) {
+		do_div(si->ec_sum, si->ec_count);
+		si->mean_ec = si->ec_sum;
+	}
 
 	if (si->is_empty)
 		ubi_msg("empty MTD device detected");
diff --git a/drivers/mtd/ubi/scan.h b/drivers/mtd/ubi/scan.h
index 46d444af471..966b9b682a4 100644
--- a/drivers/mtd/ubi/scan.h
+++ b/drivers/mtd/ubi/scan.h
@@ -124,7 +124,7 @@ struct ubi_scan_info {
 	int max_ec;
 	unsigned long long max_sqnum;
 	int mean_ec;
-	int ec_sum;
+	uint64_t ec_sum;
 	int ec_count;
 };
 
diff --git a/include/mtd/ubi-header.h b/drivers/mtd/ubi/ubi-media.h
index 292f916ea56..c3185d9fd04 100644
--- a/include/mtd/ubi-header.h
+++ b/drivers/mtd/ubi/ubi-media.h
@@ -24,11 +24,11 @@
 
 /*
  * This file defines the layout of UBI headers and all the other UBI on-flash
- * data structures. May be included by user-space.
+ * data structures.
  */
 
-#ifndef __UBI_HEADER_H__
-#define __UBI_HEADER_H__
+#ifndef __UBI_MEDIA_H__
+#define __UBI_MEDIA_H__
 
 #include <asm/byteorder.h>
 
@@ -369,4 +369,4 @@ struct ubi_vtbl_record {
 	__be32  crc;
 } __attribute__ ((packed));
 
-#endif /* !__UBI_HEADER_H__ */
+#endif /* !__UBI_MEDIA_H__ */
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index 8f095cb8710..67dcbd11c15 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -37,10 +37,9 @@
 #include <linux/string.h>
 #include <linux/vmalloc.h>
 #include <linux/mtd/mtd.h>
-
-#include <mtd/ubi-header.h>
 #include <linux/mtd/ubi.h>
 
+#include "ubi-media.h"
 #include "scan.h"
 #include "debug.h"
 
diff --git a/include/mtd/Kbuild b/include/mtd/Kbuild
index 4d46b3bdebd..8eb018f9600 100644
--- a/include/mtd/Kbuild
+++ b/include/mtd/Kbuild
@@ -3,5 +3,4 @@ header-y += jffs2-user.h
 header-y += mtd-abi.h
 header-y += mtd-user.h
 header-y += nftl-user.h
-header-y += ubi-header.h
 header-y += ubi-user.h