Tanya, On Sun, Sep 28, 2014 at 8:38 AM, Tanya Brokhman <tlinder@xxxxxxxxxxxxxx> wrote: > A given eraseblock can be read many times or not at all. > We do not have the account of such eraseblocks that have > not been accessed since a pre-defined threshold interval. > By means of scanning the entire flash device it is possible to identify > all such eraseblocks. > > Add a sysfs entry to force scan on all the PEBs on demand basis. > > The sysfs entry would be available under /sys/class/ubi/ubiX/peb_scan > - echo 1 to this entry would trigger the scan, ignored if in progress > - On reading returns the scan status (1 = Scan executing, 0 = Scan not > executing) Did you see that? http://linux-kernel.2935.n7.nabble.com/RFC-UBI-bitrot-checking-td949453.html Maybe we can combine our work. Although your patch seems to be in better shape than mine. :) > Signed-off-by: Pratibhasagar V <pratibha@xxxxxxxxxxxxxx> > Signed-off-by: Tatyana Brokhman <tlinder@xxxxxxxxxxxxxx> > --- > drivers/mtd/ubi/build.c | 32 +++++++++-- > drivers/mtd/ubi/ubi.h | 3 + > drivers/mtd/ubi/wl.c | 143 +++++++++++++++++++++++++++++++++++++++++++++++- > 3 files changed, 171 insertions(+), 7 deletions(-) > > diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c > index 34fe23a..a7464f8 100644 > --- a/drivers/mtd/ubi/build.c > +++ b/drivers/mtd/ubi/build.c > @@ -154,6 +154,9 @@ static struct device_attribute dev_dt_threshold = > static struct device_attribute dev_rd_threshold = > __ATTR(rd_threshold, (S_IWUSR | S_IRUGO), dev_attribute_show, > dev_attribute_store); > +static struct device_attribute dev_mtd_trigger_scan = > + __ATTR(peb_scan, (S_IWUSR | S_IRUGO), > + dev_attribute_show, dev_attribute_store); > > /** > * ubi_volume_notify - send a volume change notification. > @@ -395,6 +398,8 @@ static ssize_t dev_attribute_show(struct device *dev, > ret = sprintf(buf, "%d\n", ubi->dt_threshold); > else if (attr == &dev_rd_threshold) > ret = sprintf(buf, "%d\n", ubi->rd_threshold); > + else if (attr == &dev_mtd_trigger_scan) > + ret = sprintf(buf, "%d\n", ubi->scan_in_progress); > else > ret = -EINVAL; > > @@ -406,7 +411,7 @@ static ssize_t dev_attribute_store(struct device *dev, > struct device_attribute *attr, > const char *buf, size_t count) > { > - int value; > + int value, ret; > struct ubi_device *ubi; > > ubi = container_of(dev, struct ubi_device, dev); > @@ -414,8 +419,11 @@ static ssize_t dev_attribute_store(struct device *dev, > if (!ubi) > return -ENODEV; > > - if (kstrtos32(buf, 10, &value)) > - return -EINVAL; > + ret = count; > + if (kstrtos32(buf, 10, &value)) { > + ret = -EINVAL; > + goto out; > + } > /* Consider triggering full scan if threshods change */ > else if (attr == &dev_dt_threshold) { > if (value < UBI_MAX_DT_THRESHOLD) > @@ -429,9 +437,21 @@ static ssize_t dev_attribute_store(struct device *dev, > else > pr_err("Max supported threshold value is %d", > UBI_MAX_READCOUNTER); > + } else if (attr == &dev_mtd_trigger_scan) { > + if (value != 1) { > + pr_err("Invalid input. Echo 1 to start trigger"); > + goto out; > + } > + if (!ubi->lookuptbl) { > + pr_err("lookuptbl is null"); > + goto out; > + } > + ret = ubi_wl_scan_all(ubi); > } > > - return count; > +out: > + ubi_put_device(ubi); > + return ret; > } > > static void dev_release(struct device *dev) > @@ -500,6 +520,9 @@ static int ubi_sysfs_init(struct ubi_device *ubi, int *ref) > if (err) > return err; > err = device_create_file(&ubi->dev, &dev_rd_threshold); > + if (err) > + return err; > + err = device_create_file(&ubi->dev, &dev_mtd_trigger_scan); > return err; > } > > @@ -509,6 +532,7 @@ 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_trigger_scan); > device_remove_file(&ubi->dev, &dev_mtd_num); > device_remove_file(&ubi->dev, &dev_dt_threshold); > device_remove_file(&ubi->dev, &dev_rd_threshold); > diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h > index ed04de2..1079517 100644 > --- a/drivers/mtd/ubi/ubi.h > +++ b/drivers/mtd/ubi/ubi.h > @@ -491,6 +491,7 @@ struct ubi_debug_info { > * for more info > * @dt_threshold: data retention threshold. See UBI_DT_THRESHOLD > * for more info > + * @scan_in_progress: true if scanning of device PEBs is in progress > * > * @flash_size: underlying MTD device size (in bytes) > * @peb_count: count of physical eraseblocks on the MTD device > @@ -595,6 +596,7 @@ struct ubi_device { > char bgt_name[sizeof(UBI_BGT_NAME_PATTERN)+2]; > int rd_threshold; > int dt_threshold; > + bool scan_in_progress; > > > /* I/O sub-system's stuff */ > @@ -873,6 +875,7 @@ int ubi_is_erase_work(struct ubi_work *wrk); > void ubi_refill_pools(struct ubi_device *ubi); > int ubi_ensure_anchor_pebs(struct ubi_device *ubi); > int ubi_in_wl_tree(struct ubi_wl_entry *e, struct rb_root *root); > +int ubi_wl_scan_all(struct ubi_device *ubi); > > /* io.c */ > int ubi_io_read(const struct ubi_device *ubi, void *buf, int pnum, int offset, > diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c > index a5d754f..4edbb4c 100644 > --- a/drivers/mtd/ubi/wl.c > +++ b/drivers/mtd/ubi/wl.c > @@ -143,6 +143,8 @@ static int self_check_in_wl_tree(const struct ubi_device *ubi, > struct ubi_wl_entry *e, struct rb_root *root); > static int self_check_in_pq(const struct ubi_device *ubi, > struct ubi_wl_entry *e); > +static int schedule_erase(struct ubi_device *ubi, struct ubi_wl_entry *e, > + int vol_id, int lnum, int torture); > > #ifdef CONFIG_MTD_UBI_FASTMAP > /** > @@ -555,8 +557,11 @@ retry: > static void return_unused_pool_pebs(struct ubi_device *ubi, > struct ubi_fm_pool *pool) > { > - int i; > + int i, err; > struct ubi_wl_entry *e; > + struct timeval tv; > + > + do_gettimeofday(&tv); > > for (i = pool->used; i < pool->size; i++) { > e = ubi->lookuptbl[pool->pebs[i]]; > @@ -566,8 +571,22 @@ static void return_unused_pool_pebs(struct ubi_device *ubi, > self_check_in_wl_tree(ubi, e, &ubi->scrub); > rb_erase(&e->u.rb, &ubi->scrub); > } > - wl_tree_add(e, &ubi->free); > - ubi->free_count++; > + if (e->last_erase_time + UBI_DT_THRESHOLD < > + (tv.tv_sec / NUM_SEC_IN_DAY)) { > + spin_unlock(&ubi->wl_lock); > + err = schedule_erase(ubi, e, UBI_UNKNOWN, > + UBI_UNKNOWN, 0); > + spin_lock(&ubi->wl_lock); > + if (err) { > + ubi_err( > + "Failed to schedule erase for PEB %d (err=%d)", > + e->pnum, err); > + ubi_ro_mode(ubi); > + } > + } else { > + wl_tree_add(e, &ubi->free); > + ubi->free_count++; > + } > } > } > > @@ -711,6 +730,124 @@ int ubi_wl_get_peb(struct ubi_device *ubi) > #endif > > /** > + * ubi_wl_scan_all - Scan all PEB's > + * @ubi: UBI device description object > + * > + * This function scans all device PEBs in order to locate once > + * need scrubbing; due to read disturb threashold or last erase > + * timestamp. > + * > + * Return 0 in case of sucsess, (negative) error code otherwise > + * > + */ > +int ubi_wl_scan_all(struct ubi_device *ubi) > +{ > + struct timeval tv; > + struct rb_node *node; > + struct ubi_wl_entry *wl_e, *tmp; > + int used_cnt, free_cnt; > + int err; > + > + do_gettimeofday(&tv); > + if (!ubi->lookuptbl) { > + ubi_err("lookuptbl is null"); > + return -ENOENT; > + } > + > + spin_lock(&ubi->wl_lock); > + if (ubi->scan_in_progress) { > + ubi_err("Scan already in progress, ignoring the trigger"); > + err = -EPERM; > + goto out; > + } > + ubi->scan_in_progress = true; > + > + ubi_msg("Scanning all PEBs for read-disturb/erasures"); > + /* For PEBs in free list rc=0 */ > + free_cnt = 0; > + node = rb_first(&ubi->free); > + while (node) { > + wl_e = rb_entry(node, struct ubi_wl_entry, u.rb); > + node = rb_next(node); > + if (wl_e->last_erase_time + UBI_DT_THRESHOLD < > + (tv.tv_sec / NUM_SEC_IN_DAY)) { > + if (self_check_in_wl_tree(ubi, wl_e, &ubi->free)) { > + ubi_err("PEB %d moved from free tree", > + wl_e->pnum); > + err = -EAGAIN; > + goto out; > + } > + rb_erase(&wl_e->u.rb, &ubi->free); > + ubi->free_count--; > + spin_unlock(&ubi->wl_lock); > + err = schedule_erase(ubi, wl_e, UBI_UNKNOWN, > + UBI_UNKNOWN, 0); > + spin_lock(&ubi->wl_lock); > + if (err) { > + ubi_err( > + "Failed to schedule erase for PEB %d (err=%d)", > + wl_e->pnum, err); > + ubi_ro_mode(ubi); > + goto out; > + } > + free_cnt++; > + } > + } > + > + used_cnt = 0; > + node = rb_first(&ubi->used); > + while (node) { > + wl_e = rb_entry(node, struct ubi_wl_entry, u.rb); > + node = rb_next(node); > + if ((wl_e->rc >= UBI_RD_THRESHOLD) || > + (wl_e->last_erase_time + > + UBI_DT_THRESHOLD < (tv.tv_sec / NUM_SEC_IN_DAY))) { > + spin_unlock(&ubi->wl_lock); > + err = ubi_wl_scrub_peb(ubi, wl_e->pnum); > + if (err) > + ubi_err( > + "Failed to schedule scrub for PEB %d (err=%d)", > + wl_e->pnum, err); > + else > + used_cnt++; > + spin_lock(&ubi->wl_lock); > + } > + } > + > + /* Go over protection queue */ > + list_for_each_entry_safe(wl_e, tmp, &ubi->pq[ubi->pq_head], u.list) { > + if ((wl_e->rc >= UBI_RD_THRESHOLD) || > + (wl_e->last_erase_time + > + UBI_DT_THRESHOLD < (tv.tv_sec / NUM_SEC_IN_DAY))) { > + spin_unlock(&ubi->wl_lock); > + err = ubi_wl_scrub_peb(ubi, wl_e->pnum); > + if (err) > + ubi_err( > + "Failed to schedule scrub for PEB %d (err=%d)", > + wl_e->pnum, err); > + else > + used_cnt++; > + spin_lock(&ubi->wl_lock); > + } > + } > + spin_unlock(&ubi->wl_lock); > + ubi_msg("Scheduled %d for erasure", free_cnt); > + ubi_msg("Scehduled %d for scrubbing", used_cnt); > + err = ubi_wl_flush(ubi, UBI_ALL, UBI_ALL); > + if (err) > + ubi_err("Failed to flush ubi wq. err = %d", err); > + else > + ubi_msg("Flashed ubi wq"); > + > + spin_lock(&ubi->wl_lock); > +out: > + ubi->scan_in_progress = false; > + spin_unlock(&ubi->wl_lock); > + ubi_msg("Scanning all PEBs completed. err = %d", err); > + return err; > +} > + > +/** > * prot_queue_del - remove a physical eraseblock from the protection queue. > * @ubi: UBI device description object > * @pnum: the physical eraseblock to remove > -- > 1.8.5.2 > -- > QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member > of Code Aurora Forum, hosted by The Linux Foundation > > ______________________________________________________ > Linux MTD discussion mailing list > http://lists.infradead.org/mailman/listinfo/linux-mtd/ -- Thanks, //richard -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
