From f902b02600028dfc0c9df811eb711ac7d7fca09f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 14 Nov 2019 15:34:32 +0100 Subject: block: refactor rescan_partitions Split out a helper that adds one single partition, and another one calling that dealing with the parsed_partitions state. This makes it much more obvious how we clean up all state and start again when using the rescan label. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/partition-generic.c | 172 +++++++++++++++++++++++++--------------------- 1 file changed, 94 insertions(+), 78 deletions(-) (limited to 'block') diff --git a/block/partition-generic.c b/block/partition-generic.c index 31bff3fb28af..7eabb67f99b5 100644 --- a/block/partition-generic.c +++ b/block/partition-generic.c @@ -459,128 +459,144 @@ static int drop_partitions(struct gendisk *disk, struct block_device *bdev) return 0; } -int rescan_partitions(struct gendisk *disk, struct block_device *bdev) +static bool blk_add_partition(struct gendisk *disk, struct block_device *bdev, + struct parsed_partitions *state, int p) { - struct parsed_partitions *state = NULL; + sector_t size = state->parts[p].size; + sector_t from = state->parts[p].from; struct hd_struct *part; - int p, highest, res; -rescan: - if (state && !IS_ERR(state)) { - free_partitions(state); - state = NULL; + + if (!size) + return true; + + if (from >= get_capacity(disk)) { + printk(KERN_WARNING + "%s: p%d start %llu is beyond EOD, ", + disk->disk_name, p, (unsigned long long) from); + if (disk_unlock_native_capacity(disk)) + return false; + return true; } - res = drop_partitions(disk, bdev); - if (res) - return res; + if (from + size > get_capacity(disk)) { + printk(KERN_WARNING + "%s: p%d size %llu extends beyond EOD, ", + disk->disk_name, p, (unsigned long long) size); - if (disk->fops->revalidate_disk) - disk->fops->revalidate_disk(disk); - check_disk_size_change(disk, bdev, true); - bdev->bd_invalidated = 0; - if (!get_capacity(disk) || !(state = check_partition(disk, bdev))) + if (disk_unlock_native_capacity(disk)) + return false; + + /* + * We can not ignore partitions of broken tables created by for + * example camera firmware, but we limit them to the end of the + * disk to avoid creating invalid block devices. + */ + size = get_capacity(disk) - from; + } + + part = add_partition(disk, p, from, size, state->parts[p].flags, + &state->parts[p].info); + if (IS_ERR(part)) { + printk(KERN_ERR " %s: p%d could not be added: %ld\n", + disk->disk_name, p, -PTR_ERR(part)); + return true; + } + +#ifdef CONFIG_BLK_DEV_MD + if (state->parts[p].flags & ADDPART_FLAG_RAID) + md_autodetect_dev(part_to_dev(part)->devt); +#endif + return true; +} + +static int blk_add_partitions(struct gendisk *disk, struct block_device *bdev) +{ + struct parsed_partitions *state; + int ret = -EAGAIN, p, highest; + + state = check_partition(disk, bdev); + if (!state) return 0; if (IS_ERR(state)) { /* - * I/O error reading the partition table. If any - * partition code tried to read beyond EOD, retry - * after unlocking native capacity. + * I/O error reading the partition table. If we tried to read + * beyond EOD, retry after unlocking the native capacity. */ if (PTR_ERR(state) == -ENOSPC) { printk(KERN_WARNING "%s: partition table beyond EOD, ", disk->disk_name); if (disk_unlock_native_capacity(disk)) - goto rescan; + return -EAGAIN; } return -EIO; } - /* Partitions are not supported on zoned block devices */ + /* + * Partitions are not supported on zoned block devices. + */ if (bdev_is_zoned(bdev)) { pr_warn("%s: ignoring partition table on zoned block device\n", disk->disk_name); - goto out; + ret = 0; + goto out_free_state; } /* - * If any partition code tried to read beyond EOD, try - * unlocking native capacity even if partition table is - * successfully read as we could be missing some partitions. + * If we read beyond EOD, try unlocking native capacity even if the + * partition table was successfully read as we could be missing some + * partitions. */ if (state->access_beyond_eod) { printk(KERN_WARNING "%s: partition table partially beyond EOD, ", disk->disk_name); if (disk_unlock_native_capacity(disk)) - goto rescan; + goto out_free_state; } /* tell userspace that the media / partition table may have changed */ kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); - /* Detect the highest partition number and preallocate - * disk->part_tbl. This is an optimization and not strictly - * necessary. + /* + * Detect the highest partition number and preallocate disk->part_tbl. + * This is an optimization and not strictly necessary. */ for (p = 1, highest = 0; p < state->limit; p++) if (state->parts[p].size) highest = p; - disk_expand_part_tbl(disk, highest); - /* add partitions */ - for (p = 1; p < state->limit; p++) { - sector_t size, from; + for (p = 1; p < state->limit; p++) + if (!blk_add_partition(disk, bdev, state, p)) + goto out_free_state; - size = state->parts[p].size; - if (!size) - continue; + ret = 0; +out_free_state: + free_partitions(state); + return ret; +} - from = state->parts[p].from; - if (from >= get_capacity(disk)) { - printk(KERN_WARNING - "%s: p%d start %llu is beyond EOD, ", - disk->disk_name, p, (unsigned long long) from); - if (disk_unlock_native_capacity(disk)) - goto rescan; - continue; - } +int rescan_partitions(struct gendisk *disk, struct block_device *bdev) +{ + int ret; - if (from + size > get_capacity(disk)) { - printk(KERN_WARNING - "%s: p%d size %llu extends beyond EOD, ", - disk->disk_name, p, (unsigned long long) size); - - if (disk_unlock_native_capacity(disk)) { - /* free state and restart */ - goto rescan; - } else { - /* - * we can not ignore partitions of broken tables - * created by for example camera firmware, but - * we limit them to the end of the disk to avoid - * creating invalid block devices - */ - size = get_capacity(disk) - from; - } - } +rescan: + ret = drop_partitions(disk, bdev); + if (ret) + return ret; - part = add_partition(disk, p, from, size, - state->parts[p].flags, - &state->parts[p].info); - if (IS_ERR(part)) { - printk(KERN_ERR " %s: p%d could not be added: %ld\n", - disk->disk_name, p, -PTR_ERR(part)); - continue; - } -#ifdef CONFIG_BLK_DEV_MD - if (state->parts[p].flags & ADDPART_FLAG_RAID) - md_autodetect_dev(part_to_dev(part)->devt); -#endif - } -out: - free_partitions(state); - return 0; + if (disk->fops->revalidate_disk) + disk->fops->revalidate_disk(disk); + check_disk_size_change(disk, bdev, true); + bdev->bd_invalidated = 0; + + if (!get_capacity(disk)) + return 0; + + ret = blk_add_partitions(disk, bdev); + if (ret == -EAGAIN) + goto rescan; + return ret; } int invalidate_partitions(struct gendisk *disk, struct block_device *bdev) -- cgit v1.2.3 From 6917d0689993f46d97d40dd66c601d0fd5b1dbdd Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 14 Nov 2019 15:34:33 +0100 Subject: block: merge invalidate_partitions into rescan_partitions A lot of the logic in invalidate_partitions and rescan_partitions is shared. Merge the two functions to simplify things. There is a small behavior change in that we now send the kevent change notice also if we were not invalidating but no partitions were found, which seems like the right thing to do. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Jens Axboe --- block/ioctl.c | 2 +- block/partition-generic.c | 38 ++++++++++++++------------------------ 2 files changed, 15 insertions(+), 25 deletions(-) (limited to 'block') diff --git a/block/ioctl.c b/block/ioctl.c index 8756efb1419e..f6576a6d5778 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -171,7 +171,7 @@ int __blkdev_reread_part(struct block_device *bdev) lockdep_assert_held(&bdev->bd_mutex); - return rescan_partitions(disk, bdev); + return rescan_partitions(disk, bdev, false); } EXPORT_SYMBOL(__blkdev_reread_part); diff --git a/block/partition-generic.c b/block/partition-generic.c index 7eabb67f99b5..6b9f4f5d993a 100644 --- a/block/partition-generic.c +++ b/block/partition-generic.c @@ -576,7 +576,8 @@ out_free_state: return ret; } -int rescan_partitions(struct gendisk *disk, struct block_device *bdev) +int rescan_partitions(struct gendisk *disk, struct block_device *bdev, + bool invalidate) { int ret; @@ -585,13 +586,22 @@ rescan: if (ret) return ret; - if (disk->fops->revalidate_disk) + if (invalidate) + set_capacity(disk, 0); + else if (disk->fops->revalidate_disk) disk->fops->revalidate_disk(disk); - check_disk_size_change(disk, bdev, true); + + check_disk_size_change(disk, bdev, !invalidate); bdev->bd_invalidated = 0; - if (!get_capacity(disk)) + if (!get_capacity(disk)) { + /* + * Tell userspace that the media / partition table may have + * changed. + */ + kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); return 0; + } ret = blk_add_partitions(disk, bdev); if (ret == -EAGAIN) @@ -599,26 +609,6 @@ rescan: return ret; } -int invalidate_partitions(struct gendisk *disk, struct block_device *bdev) -{ - int res; - - if (!bdev->bd_invalidated) - return 0; - - res = drop_partitions(disk, bdev); - if (res) - return res; - - set_capacity(disk, 0); - check_disk_size_change(disk, bdev, false); - bdev->bd_invalidated = 0; - /* tell userspace that the media / partition table may have changed */ - kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); - - return 0; -} - unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p) { struct address_space *mapping = bdev->bd_inode->i_mapping; -- cgit v1.2.3 From a1548b674403c0de70cc29a1575689917ba60157 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 14 Nov 2019 15:34:34 +0100 Subject: block: move rescan_partitions to fs/block_dev.c Large parts of rescan_partitions aren't about partitions, and moving it to block_dev.c will allow for some further cleanups by merging it into its only caller. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Jens Axboe --- block/partition-generic.c | 37 ++----------------------------------- 1 file changed, 2 insertions(+), 35 deletions(-) (limited to 'block') diff --git a/block/partition-generic.c b/block/partition-generic.c index 6b9f4f5d993a..2cbc23f6032c 100644 --- a/block/partition-generic.c +++ b/block/partition-generic.c @@ -439,7 +439,7 @@ static bool disk_unlock_native_capacity(struct gendisk *disk) } } -static int drop_partitions(struct gendisk *disk, struct block_device *bdev) +int blk_drop_partitions(struct gendisk *disk, struct block_device *bdev) { struct disk_part_iter piter; struct hd_struct *part; @@ -509,7 +509,7 @@ static bool blk_add_partition(struct gendisk *disk, struct block_device *bdev, return true; } -static int blk_add_partitions(struct gendisk *disk, struct block_device *bdev) +int blk_add_partitions(struct gendisk *disk, struct block_device *bdev) { struct parsed_partitions *state; int ret = -EAGAIN, p, highest; @@ -576,39 +576,6 @@ out_free_state: return ret; } -int rescan_partitions(struct gendisk *disk, struct block_device *bdev, - bool invalidate) -{ - int ret; - -rescan: - ret = drop_partitions(disk, bdev); - if (ret) - return ret; - - if (invalidate) - set_capacity(disk, 0); - else if (disk->fops->revalidate_disk) - disk->fops->revalidate_disk(disk); - - check_disk_size_change(disk, bdev, !invalidate); - bdev->bd_invalidated = 0; - - if (!get_capacity(disk)) { - /* - * Tell userspace that the media / partition table may have - * changed. - */ - kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); - return 0; - } - - ret = blk_add_partitions(disk, bdev); - if (ret == -EAGAIN) - goto rescan; - return ret; -} - unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p) { struct address_space *mapping = bdev->bd_inode->i_mapping; -- cgit v1.2.3 From 142fe8f4bb169e8632024d51c64653a8bf140561 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 14 Nov 2019 15:34:35 +0100 Subject: block: fix bdev_disk_changed for non-partitioned devices We still have to set the capacity to 0 if invalidating or call revalidate_disk if not even if the disk has no partitions. Fix that by merging rescan_partitions into bdev_disk_changed and just stubbing out blk_add_partitions and blk_drop_partitions for non-partitioned devices. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Signed-off-by: Jens Axboe --- block/ioctl.c | 6 ++---- block/partition-generic.c | 5 +++++ 2 files changed, 7 insertions(+), 4 deletions(-) (limited to 'block') diff --git a/block/ioctl.c b/block/ioctl.c index f6576a6d5778..5ccd9f016594 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -162,16 +162,14 @@ static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user */ int __blkdev_reread_part(struct block_device *bdev) { - struct gendisk *disk = bdev->bd_disk; - - if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains) + if (!disk_part_scan_enabled(bdev->bd_disk) || bdev != bdev->bd_contains) return -EINVAL; if (!capable(CAP_SYS_ADMIN)) return -EACCES; lockdep_assert_held(&bdev->bd_mutex); - return rescan_partitions(disk, bdev, false); + return bdev_disk_changed(bdev, false); } EXPORT_SYMBOL(__blkdev_reread_part); diff --git a/block/partition-generic.c b/block/partition-generic.c index 2cbc23f6032c..61487421a319 100644 --- a/block/partition-generic.c +++ b/block/partition-generic.c @@ -445,6 +445,8 @@ int blk_drop_partitions(struct gendisk *disk, struct block_device *bdev) struct hd_struct *part; int res; + if (!disk_part_scan_enabled(disk)) + return 0; if (bdev->bd_part_count || bdev->bd_super) return -EBUSY; res = invalidate_partition(disk, 0); @@ -514,6 +516,9 @@ int blk_add_partitions(struct gendisk *disk, struct block_device *bdev) struct parsed_partitions *state; int ret = -EAGAIN, p, highest; + if (!disk_part_scan_enabled(disk)) + return 0; + state = check_partition(disk, bdev); if (!state) return 0; -- cgit v1.2.3 From f0b870df80bc70dad432fd0c142bb709a49964f5 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 14 Nov 2019 15:34:36 +0100 Subject: block: remove (__)blkdev_reread_part as an exported API In general drivers should never mess with partition tables directly. Unfortunately s390 and loop do for somewhat historic reasons, but they can use bdev_disk_changed directly instead when we export it as they satisfy the sanity checks we have in __blkdev_reread_part. Signed-off-by: Christoph Hellwig Reviewed-by: Stefan Haberland [dasd] Reviewed-by: Jan Kara Signed-off-by: Jens Axboe --- block/ioctl.c | 35 +++++------------------------------ 1 file changed, 5 insertions(+), 30 deletions(-) (limited to 'block') diff --git a/block/ioctl.c b/block/ioctl.c index 5ccd9f016594..7ac8a66c9787 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -155,46 +155,21 @@ static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user } } -/* - * This is an exported API for the block driver, and will not - * acquire bd_mutex. This API should be used in case that - * caller has held bd_mutex already. - */ -int __blkdev_reread_part(struct block_device *bdev) +static int blkdev_reread_part(struct block_device *bdev) { + int ret; + if (!disk_part_scan_enabled(bdev->bd_disk) || bdev != bdev->bd_contains) return -EINVAL; if (!capable(CAP_SYS_ADMIN)) return -EACCES; - lockdep_assert_held(&bdev->bd_mutex); - - return bdev_disk_changed(bdev, false); -} -EXPORT_SYMBOL(__blkdev_reread_part); - -/* - * This is an exported API for the block driver, and will - * try to acquire bd_mutex. If bd_mutex has been held already - * in current context, please call __blkdev_reread_part(). - * - * Make sure the held locks in current context aren't required - * in open()/close() handler and I/O path for avoiding ABBA deadlock: - * - bd_mutex is held before calling block driver's open/close - * handler - * - reading partition table may submit I/O to the block device - */ -int blkdev_reread_part(struct block_device *bdev) -{ - int res; - mutex_lock(&bdev->bd_mutex); - res = __blkdev_reread_part(bdev); + ret = bdev_disk_changed(bdev, false); mutex_unlock(&bdev->bd_mutex); - return res; + return ret; } -EXPORT_SYMBOL(blkdev_reread_part); static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode, unsigned long arg, unsigned long flags) -- cgit v1.2.3