[RFC/PATCH 1/5] mtd: ubi: Read disturb infrastructure
Richard Weinberger
richard at nod.at
Sun Sep 28 01:18:36 PDT 2014
Tanya,
Am 28.09.2014 08:37, schrieb Tanya Brokhman:
> The need for performing read disturb is determined according to new
> statistics collected per eraseblock:
> - read counter: incremented at each read operation
> reset at each erase
> - last erase time stamp: updated at each erase
> This patch adds the infrastructure for the above statistics
>
> Signed-off-by: Tanya Brokhman <tlinder at codeaurora.org>
> ---
> drivers/mtd/ubi/build.c | 57 +++++++++++++++++++++++++++++++++++++++++++++
> drivers/mtd/ubi/fastmap.c | 14 +++++++----
> drivers/mtd/ubi/ubi-media.h | 32 ++++++++++++++++++++++---
> drivers/mtd/ubi/ubi.h | 34 +++++++++++++++++++++++++++
> drivers/mtd/ubi/wl.c | 6 +++++
> 5 files changed, 135 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
> index 6e30a3c..34fe23a 100644
> --- a/drivers/mtd/ubi/build.c
> +++ b/drivers/mtd/ubi/build.c
> @@ -1,6 +1,9 @@
> /*
> * Copyright (c) International Business Machines Corp., 2006
> * Copyright (c) Nokia Corporation, 2007
> + * 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
> @@ -118,6 +121,10 @@ static struct class_attribute ubi_version =
> static ssize_t dev_attribute_show(struct device *dev,
> struct device_attribute *attr, char *buf);
>
> +static ssize_t dev_attribute_store(struct device *dev,
> + struct device_attribute *attr, const char *buf,
> + size_t count);
> +
> /* UBI device attributes (correspond to files in '/<sysfs>/class/ubi/ubiX') */
> static struct device_attribute dev_eraseblock_size =
> __ATTR(eraseblock_size, S_IRUGO, dev_attribute_show, NULL);
> @@ -141,6 +148,12 @@ static struct device_attribute dev_bgt_enabled =
> __ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
> static struct device_attribute dev_mtd_num =
> __ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
> +static struct device_attribute dev_dt_threshold =
> + __ATTR(dt_threshold, (S_IWUSR | S_IRUGO), dev_attribute_show,
> + dev_attribute_store);
> +static struct device_attribute dev_rd_threshold =
> + __ATTR(rd_threshold, (S_IWUSR | S_IRUGO), dev_attribute_show,
> + dev_attribute_store);
>
> /**
> * ubi_volume_notify - send a volume change notification.
> @@ -378,6 +391,10 @@ static ssize_t dev_attribute_show(struct device *dev,
> ret = sprintf(buf, "%d\n", ubi->thread_enabled);
> else if (attr == &dev_mtd_num)
> ret = sprintf(buf, "%d\n", ubi->mtd->index);
> + else if (attr == &dev_dt_threshold)
> + ret = sprintf(buf, "%d\n", ubi->dt_threshold);
> + else if (attr == &dev_rd_threshold)
> + ret = sprintf(buf, "%d\n", ubi->rd_threshold);
> else
> ret = -EINVAL;
>
> @@ -385,6 +402,38 @@ static ssize_t dev_attribute_show(struct device *dev,
> return ret;
> }
>
> +static ssize_t dev_attribute_store(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t count)
> +{
> + int value;
> + struct ubi_device *ubi;
> +
> + ubi = container_of(dev, struct ubi_device, dev);
> + ubi = ubi_get_device(ubi->ubi_num);
> + if (!ubi)
> + return -ENODEV;
> +
> + if (kstrtos32(buf, 10, &value))
> + return -EINVAL;
> + /* Consider triggering full scan if threshods change */
> + else if (attr == &dev_dt_threshold) {
> + if (value < UBI_MAX_DT_THRESHOLD)
> + ubi->dt_threshold = value;
> + else
> + pr_err("Max supported threshold value is %d",
> + UBI_MAX_DT_THRESHOLD);
> + } else if (attr == &dev_rd_threshold) {
> + if (value < UBI_MAX_READCOUNTER)
> + ubi->rd_threshold = value;
> + else
> + pr_err("Max supported threshold value is %d",
> + UBI_MAX_READCOUNTER);
> + }
> +
> + return count;
> +}
> +
> static void dev_release(struct device *dev)
> {
> struct ubi_device *ubi = container_of(dev, struct ubi_device, dev);
> @@ -445,6 +494,12 @@ static int ubi_sysfs_init(struct ubi_device *ubi, int *ref)
> if (err)
> return err;
> err = device_create_file(&ubi->dev, &dev_mtd_num);
> + if (err)
> + return err;
> + err = device_create_file(&ubi->dev, &dev_dt_threshold);
> + if (err)
> + return err;
> + err = device_create_file(&ubi->dev, &dev_rd_threshold);
> return err;
> }
>
> @@ -455,6 +510,8 @@ static int ubi_sysfs_init(struct ubi_device *ubi, int *ref)
> static void ubi_sysfs_close(struct ubi_device *ubi)
> {
> device_remove_file(&ubi->dev, &dev_mtd_num);
> + device_remove_file(&ubi->dev, &dev_dt_threshold);
> + device_remove_file(&ubi->dev, &dev_rd_threshold);
> device_remove_file(&ubi->dev, &dev_bgt_enabled);
> device_remove_file(&ubi->dev, &dev_min_io_size);
> device_remove_file(&ubi->dev, &dev_max_vol_count);
> diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c
> 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.
> * Author: Richard Weinberger <richard at nod.at>
> *
> * 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?
> __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.
> } __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.
Thanks,
//richard
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