diff options
author | Vishal Verma <vishal.l.verma@intel.com> | 2016-01-09 17:36:51 +0100 |
---|---|---|
committer | Dan Williams <dan.j.williams@intel.com> | 2016-01-09 17:36:51 +0100 |
commit | 99e6608c9e7414ae4f2168df8bf8fae3eb49e41f (patch) | |
tree | 20ab40762557164e1358a960782410c33bd4f423 /block | |
parent | badblocks: Add core badblock management code (diff) | |
download | linux-99e6608c9e7414ae4f2168df8bf8fae3eb49e41f.tar.xz linux-99e6608c9e7414ae4f2168df8bf8fae3eb49e41f.zip |
block: Add badblock management for gendisks
NVDIMM devices, which can behave more like DRAM rather than block
devices, may develop bad cache lines, or 'poison'. A block device
exposed by the pmem driver can then consume poison via a read (or
write), and cause a machine check. On platforms without machine
check recovery features, this would mean a crash.
The block device maintaining a runtime list of all known sectors that
have poison can directly avoid this, and also provide a path forward
to enable proper handling/recovery for DAX faults on such a device.
Use the new badblock management interfaces to add a badblocks list to
gendisks.
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'block')
-rw-r--r-- | block/genhd.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/block/genhd.c b/block/genhd.c index 1a971bebbbfe..88579cf373b8 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -20,6 +20,7 @@ #include <linux/idr.h> #include <linux/log2.h> #include <linux/pm_runtime.h> +#include <linux/badblocks.h> #include "blk.h" @@ -505,6 +506,16 @@ static int exact_lock(dev_t devt, void *data) return 0; } +int disk_alloc_badblocks(struct gendisk *disk) +{ + disk->bb = kzalloc(sizeof(*(disk->bb)), GFP_KERNEL); + if (!disk->bb) + return -ENOMEM; + + return badblocks_init(disk->bb, 1); +} +EXPORT_SYMBOL(disk_alloc_badblocks); + static void register_disk(struct gendisk *disk) { struct device *ddev = disk_to_dev(disk); @@ -659,6 +670,11 @@ void del_gendisk(struct gendisk *disk) blk_unregister_queue(disk); blk_unregister_region(disk_devt(disk), disk->minors); + if (disk->bb) { + badblocks_free(disk->bb); + kfree(disk->bb); + } + part_stat_set_all(&disk->part0, 0); disk->part0.stamp = 0; @@ -671,6 +687,63 @@ void del_gendisk(struct gendisk *disk) } EXPORT_SYMBOL(del_gendisk); +/* + * The gendisk usage of badblocks does not track acknowledgements for + * badblocks. We always assume they are acknowledged. + */ +int disk_check_badblocks(struct gendisk *disk, sector_t s, int sectors, + sector_t *first_bad, int *bad_sectors) +{ + if (!disk->bb) + return 0; + + return badblocks_check(disk->bb, s, sectors, first_bad, bad_sectors); +} +EXPORT_SYMBOL(disk_check_badblocks); + +int disk_set_badblocks(struct gendisk *disk, sector_t s, int sectors) +{ + if (!disk->bb) + return 0; + + return badblocks_set(disk->bb, s, sectors, 1); +} +EXPORT_SYMBOL(disk_set_badblocks); + +int disk_clear_badblocks(struct gendisk *disk, sector_t s, int sectors) +{ + if (!disk->bb) + return 0; + + return badblocks_clear(disk->bb, s, sectors); +} +EXPORT_SYMBOL(disk_clear_badblocks); + +/* sysfs access to bad-blocks list. */ +static ssize_t disk_badblocks_show(struct device *dev, + struct device_attribute *attr, + char *page) +{ + struct gendisk *disk = dev_to_disk(dev); + + if (!disk->bb) + return sprintf(page, "\n"); + + return badblocks_show(disk->bb, page, 0); +} + +static ssize_t disk_badblocks_store(struct device *dev, + struct device_attribute *attr, + const char *page, size_t len) +{ + struct gendisk *disk = dev_to_disk(dev); + + if (!disk->bb) + return -ENXIO; + + return badblocks_store(disk->bb, page, len, 0); +} + /** * get_gendisk - get partitioning information for a given device * @devt: device to get partitioning information for @@ -989,6 +1062,8 @@ static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show, static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL); static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL); static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL); +static DEVICE_ATTR(badblocks, S_IRUGO | S_IWUSR, disk_badblocks_show, + disk_badblocks_store); #ifdef CONFIG_FAIL_MAKE_REQUEST static struct device_attribute dev_attr_fail = __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store); @@ -1010,6 +1085,7 @@ static struct attribute *disk_attrs[] = { &dev_attr_capability.attr, &dev_attr_stat.attr, &dev_attr_inflight.attr, + &dev_attr_badblocks.attr, #ifdef CONFIG_FAIL_MAKE_REQUEST &dev_attr_fail.attr, #endif |