From 517bf3c306bad4fe0da631f90ae2ec40924dee2b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 2 Nov 2017 21:29:52 +0300 Subject: block: don't look at the struct device dev_t in disk_devt The hidden gendisks introduced in the next patch need to keep the dev field in their struct device empty so that udev won't try to create block device nodes for them. To support that rewrite disk_devt to look at the major and first_minor fields in the gendisk itself instead of looking into the struct device. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- include/linux/genhd.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/genhd.h') diff --git a/include/linux/genhd.h b/include/linux/genhd.h index ea652bfcd675..5c0ed5db33c2 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -234,7 +234,7 @@ static inline bool disk_part_scan_enabled(struct gendisk *disk) static inline dev_t disk_devt(struct gendisk *disk) { - return disk_to_dev(disk)->devt; + return MKDEV(disk->major, disk->first_minor); } static inline dev_t part_devt(struct hd_struct *part) -- cgit v1.2.3 From 8ddcd653257c18a669fcb75ee42c37054908e0d6 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 2 Nov 2017 21:29:53 +0300 Subject: block: introduce GENHD_FL_HIDDEN With this flag a driver can create a gendisk that can be used for I/O submission inside the kernel, but which is not registered as user facing block device. This will be useful for the NVMe multipath implementation. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/genhd.c | 68 +++++++++++++++++++++++++++++++++++++-------------- include/linux/genhd.h | 1 + 2 files changed, 51 insertions(+), 18 deletions(-) (limited to 'include/linux/genhd.h') diff --git a/block/genhd.c b/block/genhd.c index 1174d24e405e..835e907e6e01 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -585,6 +585,11 @@ static void register_disk(struct device *parent, struct gendisk *disk) */ pm_runtime_set_memalloc_noio(ddev, true); + if (disk->flags & GENHD_FL_HIDDEN) { + dev_set_uevent_suppress(ddev, 0); + return; + } + disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj); disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj); @@ -616,6 +621,11 @@ exit: while ((part = disk_part_iter_next(&piter))) kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD); disk_part_iter_exit(&piter); + + err = sysfs_create_link(&ddev->kobj, + &disk->queue->backing_dev_info->dev->kobj, + "bdi"); + WARN_ON(err); } /** @@ -630,7 +640,6 @@ exit: */ void device_add_disk(struct device *parent, struct gendisk *disk) { - struct backing_dev_info *bdi; dev_t devt; int retval; @@ -639,7 +648,8 @@ void device_add_disk(struct device *parent, struct gendisk *disk) * parameters make sense. */ WARN_ON(disk->minors && !(disk->major || disk->first_minor)); - WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT)); + WARN_ON(!disk->minors && + !(disk->flags & (GENHD_FL_EXT_DEVT | GENHD_FL_HIDDEN))); disk->flags |= GENHD_FL_UP; @@ -648,18 +658,26 @@ void device_add_disk(struct device *parent, struct gendisk *disk) WARN_ON(1); return; } - disk_to_dev(disk)->devt = devt; disk->major = MAJOR(devt); disk->first_minor = MINOR(devt); disk_alloc_events(disk); - /* Register BDI before referencing it from bdev */ - bdi = disk->queue->backing_dev_info; - bdi_register_owner(bdi, disk_to_dev(disk)); - - blk_register_region(disk_devt(disk), disk->minors, NULL, - exact_match, exact_lock, disk); + if (disk->flags & GENHD_FL_HIDDEN) { + /* + * Don't let hidden disks show up in /proc/partitions, + * and don't bother scanning for partitions either. + */ + disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO; + disk->flags |= GENHD_FL_NO_PART_SCAN; + } else { + /* Register BDI before referencing it from bdev */ + disk_to_dev(disk)->devt = devt; + bdi_register_owner(disk->queue->backing_dev_info, + disk_to_dev(disk)); + blk_register_region(disk_devt(disk), disk->minors, NULL, + exact_match, exact_lock, disk); + } register_disk(parent, disk); blk_register_queue(disk); @@ -669,10 +687,6 @@ void device_add_disk(struct device *parent, struct gendisk *disk) */ WARN_ON_ONCE(!blk_get_queue(disk->queue)); - retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj, - "bdi"); - WARN_ON(retval); - disk_add_events(disk); blk_integrity_add(disk); } @@ -701,7 +715,8 @@ void del_gendisk(struct gendisk *disk) set_capacity(disk, 0); disk->flags &= ~GENHD_FL_UP; - sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi"); + if (!(disk->flags & GENHD_FL_HIDDEN)) + sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi"); if (disk->queue) { /* * Unregister bdi before releasing device numbers (as they can @@ -712,13 +727,15 @@ void del_gendisk(struct gendisk *disk) } else { WARN_ON(1); } - blk_unregister_region(disk_devt(disk), disk->minors); + + if (!(disk->flags & GENHD_FL_HIDDEN)) { + blk_unregister_region(disk_devt(disk), disk->minors); + kobject_put(disk->part0.holder_dir); + kobject_put(disk->slave_dir); + } part_stat_set_all(&disk->part0, 0); disk->part0.stamp = 0; - - kobject_put(disk->part0.holder_dir); - kobject_put(disk->slave_dir); if (!sysfs_deprecated) sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk))); pm_runtime_set_memalloc_noio(disk_to_dev(disk), false); @@ -781,6 +798,10 @@ struct gendisk *get_gendisk(dev_t devt, int *partno) spin_unlock_bh(&ext_devt_lock); } + if (unlikely(disk->flags & GENHD_FL_HIDDEN)) { + put_disk(disk); + disk = NULL; + } return disk; } EXPORT_SYMBOL(get_gendisk); @@ -1024,6 +1045,15 @@ static ssize_t disk_removable_show(struct device *dev, (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0)); } +static ssize_t disk_hidden_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct gendisk *disk = dev_to_disk(dev); + + return sprintf(buf, "%d\n", + (disk->flags & GENHD_FL_HIDDEN ? 1 : 0)); +} + static ssize_t disk_ro_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -1061,6 +1091,7 @@ static ssize_t disk_discard_alignment_show(struct device *dev, static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL); static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL); static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL); +static DEVICE_ATTR(hidden, S_IRUGO, disk_hidden_show, NULL); static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL); static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL); static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL); @@ -1085,6 +1116,7 @@ static struct attribute *disk_attrs[] = { &dev_attr_range.attr, &dev_attr_ext_range.attr, &dev_attr_removable.attr, + &dev_attr_hidden.attr, &dev_attr_ro.attr, &dev_attr_size.attr, &dev_attr_alignment_offset.attr, diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 5c0ed5db33c2..93aae3476f58 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -140,6 +140,7 @@ struct hd_struct { #define GENHD_FL_NATIVE_CAPACITY 128 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE 256 #define GENHD_FL_NO_PART_SCAN 512 +#define GENHD_FL_HIDDEN 1024 enum { DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */ -- cgit v1.2.3 From 67f2519fe2903c4041c0e94394d14d372fe51399 Mon Sep 17 00:00:00 2001 From: Greg Edwards Date: Tue, 24 Oct 2017 11:21:48 -0600 Subject: fs: guard_bio_eod() needs to consider partitions guard_bio_eod() needs to look at the partition capacity, not just the capacity of the whole device, when determining if truncation is necessary. [ 60.268688] attempt to access beyond end of device [ 60.268690] unknown-block(9,1): rw=0, want=67103509, limit=67103506 [ 60.268693] buffer_io_error: 2 callbacks suppressed [ 60.268696] Buffer I/O error on dev md1p7, logical block 4524305, async page read Fixes: 74d46992e0d9 ("block: replace bi_bdev with a gendisk pointer and partitions index") Cc: stable@vger.kernel.org # v4.13 Reviewed-by: Christoph Hellwig Signed-off-by: Greg Edwards Signed-off-by: Jens Axboe --- fs/buffer.c | 10 +++++++++- include/linux/genhd.h | 1 + 2 files changed, 10 insertions(+), 1 deletion(-) (limited to 'include/linux/genhd.h') diff --git a/fs/buffer.c b/fs/buffer.c index bff571dc7bc3..bcabb69e7462 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -3015,8 +3015,16 @@ void guard_bio_eod(int op, struct bio *bio) sector_t maxsector; struct bio_vec *bvec = &bio->bi_io_vec[bio->bi_vcnt - 1]; unsigned truncated_bytes; + struct hd_struct *part; + + rcu_read_lock(); + part = __disk_get_part(bio->bi_disk, bio->bi_partno); + if (part) + maxsector = part_nr_sects_read(part); + else + maxsector = get_capacity(bio->bi_disk); + rcu_read_unlock(); - maxsector = get_capacity(bio->bi_disk); if (!maxsector) return; diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 93aae3476f58..ca10cc292187 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -243,6 +243,7 @@ static inline dev_t part_devt(struct hd_struct *part) return part_to_dev(part)->devt; } +extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno); extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno); static inline void disk_put_part(struct hd_struct *part) -- cgit v1.2.3