Re: [RFC/PATCH 1/5] mtd: ubi: Read disturb infrastructure
From: Tanya Brokhman
Date: Sun Sep 28 2014 - 04:48:58 EST
Hi Richard
On 9/28/2014 11:18 AM, Richard Weinberger wrote:
index 0431b46..5399aa2 100644
--- a/drivers/mtd/ubi/fastmap.c
+++ b/drivers/mtd/ubi/fastmap.c
@@ -1,5 +1,7 @@
/*
* Copyright (c) 2012 Linutronix GmbH
+ * Copyright (c) 2014, Linux Foundation. All rights reserved.
+ *
Diffstat says "drivers/mtd/ubi/fastmap.c | 14 +++++++----", does this really justify
a new copyright line?
If so I'll have to add the new company I work for here too.
You're right. my bad. added it at the beginning but decides against it
later on. Will remove.
* Author: Richard Weinberger <richard@xxxxxx>
*
* This program is free software; you can redistribute it and/or modify
@@ -727,9 +729,9 @@ static int ubi_attach_fastmap(struct ubi_device *ubi,
}
for (j = 0; j < be32_to_cpu(fm_eba->reserved_pebs); j++) {
- int pnum = be32_to_cpu(fm_eba->pnum[j]);
+ int pnum = be32_to_cpu(fm_eba->peb_data[j].pnum);
- if ((int)be32_to_cpu(fm_eba->pnum[j]) < 0)
+ if ((int)be32_to_cpu(fm_eba->peb_data[j].pnum) < 0)
continue;
aeb = NULL;
@@ -757,7 +759,8 @@ static int ubi_attach_fastmap(struct ubi_device *ubi,
}
aeb->lnum = j;
- aeb->pnum = be32_to_cpu(fm_eba->pnum[j]);
+ aeb->pnum =
+ be32_to_cpu(fm_eba->peb_data[j].pnum);
aeb->ec = -1;
aeb->scrub = aeb->copy_flag = aeb->sqnum = 0;
list_add_tail(&aeb->u.list, &eba_orphans);
@@ -1250,11 +1253,12 @@ static int ubi_write_fastmap(struct ubi_device *ubi,
vol->vol_type == UBI_STATIC_VOLUME);
feba = (struct ubi_fm_eba *)(fm_raw + fm_pos);
- fm_pos += sizeof(*feba) + (sizeof(__be32) * vol->reserved_pebs);
+ fm_pos += sizeof(*feba) +
+ 2 * (sizeof(__be32) * vol->reserved_pebs);
ubi_assert(fm_pos <= ubi->fm_size);
for (j = 0; j < vol->reserved_pebs; j++)
- feba->pnum[j] = cpu_to_be32(vol->eba_tbl[j]);
+ feba->peb_data[j].pnum = cpu_to_be32(vol->eba_tbl[j]);
feba->reserved_pebs = cpu_to_be32(j);
feba->magic = cpu_to_be32(UBI_FM_EBA_MAGIC);
diff --git a/drivers/mtd/ubi/ubi-media.h b/drivers/mtd/ubi/ubi-media.h
index ac2b24d..da418ad 100644
--- a/drivers/mtd/ubi/ubi-media.h
+++ b/drivers/mtd/ubi/ubi-media.h
@@ -1,5 +1,8 @@
/*
* Copyright (c) International Business Machines Corp., 2006
+ * Copyright (c) 2014, Linux Foundation. All rights reserved.
+ * Linux Foundation chooses to take subject only to the GPLv2
+ * license terms, and distributes only under these terms.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -38,6 +41,15 @@
/* The highest erase counter value supported by this implementation */
#define UBI_MAX_ERASECOUNTER 0x7FFFFFFF
+/* The highest read counter value supported by this implementation */
+#define UBI_MAX_READCOUNTER 0x7FFFFFFD /* (0x7FFFFFFF - 2)*/
+
+/*
+ * The highest data retention threshold value supported
+ * by this implementation
+ */
+#define UBI_MAX_DT_THRESHOLD 0x7FFFFFFF
+
/* The initial CRC32 value used when calculating CRC checksums */
#define UBI_CRC32_INIT 0xFFFFFFFFU
@@ -130,6 +142,7 @@ enum {
* @vid_hdr_offset: where the VID header starts
* @data_offset: where the user data start
* @image_seq: image sequence number
+ * @last_erase_time: time stamp of the last erase operation
* @padding2: reserved for future, zeroes
* @hdr_crc: erase counter header CRC checksum
*
@@ -162,7 +175,8 @@ struct ubi_ec_hdr {
__be32 vid_hdr_offset;
__be32 data_offset;
__be32 image_seq;
- __u8 padding2[32];
+ __be64 last_erase_time; /*curr time in sec == unsigned long time_t*/
+ __u8 padding2[24];
__be32 hdr_crc;
} __packed;
@@ -413,6 +427,8 @@ struct ubi_vtbl_record {
* @used_blocks: number of PEBs used by this fastmap
* @block_loc: an array containing the location of all PEBs of the fastmap
* @block_ec: the erase counter of each used PEB
+ * @block_rc: the read counter of each used PEB
+ * @block_let: the last erase timestamp of each used PEB
* @sqnum: highest sequence number value at the time while taking the fastmap
*
*/
@@ -424,6 +440,8 @@ struct ubi_fm_sb {
__be32 used_blocks;
__be32 block_loc[UBI_FM_MAX_BLOCKS];
__be32 block_ec[UBI_FM_MAX_BLOCKS];
+ __be32 block_rc[UBI_FM_MAX_BLOCKS];
+ __be64 block_let[UBI_FM_MAX_BLOCKS];
Doesn't this break the fastmap on-disk layout?
What do you mean "break"? I verified fastmap feature is working. the
whole read-disturb depends on it so I tested this thoroughly.
__be64 sqnum;
__u8 padding2[32];
} __packed;
@@ -469,13 +487,17 @@ struct ubi_fm_scan_pool {
/* ubi_fm_scan_pool is followed by nfree+nused struct ubi_fm_ec records */
/**
- * struct ubi_fm_ec - stores the erase counter of a PEB
+ * struct ubi_fm_ec - stores the erase/read counter of a PEB
* @pnum: PEB number
* @ec: ec of this PEB
+ * @rc: rc of this PEB
+ * @last_erase_time: last erase time stamp of this PEB
*/
struct ubi_fm_ec {
__be32 pnum;
__be32 ec;
+ __be32 rc;
+ __be64 last_erase_time;
Same here.
fastmap was thoroughly tested. all works.
} __packed;
/**
@@ -506,10 +528,14 @@ struct ubi_fm_volhdr {
* @magic: EBA table magic number
* @reserved_pebs: number of table entries
* @pnum: PEB number of LEB (LEB is the index)
+ * @rc: Read counter of the LEBs PEB (LEB is the index)
*/
struct ubi_fm_eba {
__be32 magic;
__be32 reserved_pebs;
- __be32 pnum[0];
+ struct {
+ __be32 pnum;
+ __be32 rc;
+ } peb_data[0];
And here.
fastmap was thoroughly tested. all works.
Thanks,
//richard
______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/
--
Employee of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
hosted by The Linux Foundation
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/