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author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-21 20:02:48 +0100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-21 20:02:48 +0100 |
commit | 582cd91f69de8e44857cb610ebca661dac8656b7 (patch) | |
tree | 0d680db02a5c236ee87b408b3f13ce33ebaca907 /block/genhd.c | |
parent | Merge tag 'for-5.12/libata-2021-02-17' of git://git.kernel.dk/linux-block (diff) | |
parent | mm: simplify swapdev_block (diff) | |
download | linux-582cd91f69de8e44857cb610ebca661dac8656b7.tar.xz linux-582cd91f69de8e44857cb610ebca661dac8656b7.zip |
Merge tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:
"Another nice round of removing more code than what is added, mostly
due to Christoph's relentless pursuit of tech debt removal/cleanups.
This pull request contains:
- Two series of BFQ improvements (Paolo, Jan, Jia)
- Block iov_iter improvements (Pavel)
- bsg error path fix (Pan)
- blk-mq scheduler improvements (Jan)
- -EBUSY discard fix (Jan)
- bvec allocation improvements (Ming, Christoph)
- bio allocation and init improvements (Christoph)
- Store bdev pointer in bio instead of gendisk + partno (Christoph)
- Block trace point cleanups (Christoph)
- hard read-only vs read-only split (Christoph)
- Block based swap cleanups (Christoph)
- Zoned write granularity support (Damien)
- Various fixes/tweaks (Chunguang, Guoqing, Lei, Lukas, Huhai)"
* tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block: (104 commits)
mm: simplify swapdev_block
sd_zbc: clear zone resources for non-zoned case
block: introduce blk_queue_clear_zone_settings()
zonefs: use zone write granularity as block size
block: introduce zone_write_granularity limit
block: use blk_queue_set_zoned in add_partition()
nullb: use blk_queue_set_zoned() to setup zoned devices
nvme: cleanup zone information initialization
block: document zone_append_max_bytes attribute
block: use bi_max_vecs to find the bvec pool
md/raid10: remove dead code in reshape_request
block: mark the bio as cloned in bio_iov_bvec_set
block: set BIO_NO_PAGE_REF in bio_iov_bvec_set
block: remove a layer of indentation in bio_iov_iter_get_pages
block: turn the nr_iovecs argument to bio_alloc* into an unsigned short
block: remove the 1 and 4 vec bvec_slabs entries
block: streamline bvec_alloc
block: factor out a bvec_alloc_gfp helper
block: move struct biovec_slab to bio.c
block: reuse BIO_INLINE_VECS for integrity bvecs
...
Diffstat (limited to 'block/genhd.c')
-rw-r--r-- | block/genhd.c | 306 |
1 files changed, 49 insertions, 257 deletions
diff --git a/block/genhd.c b/block/genhd.c index 9e741a4f351b..36ff45bbaaaf 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -162,15 +162,6 @@ static void part_in_flight_rw(struct block_device *part, inflight[1] = 0; } -struct block_device *__disk_get_part(struct gendisk *disk, int partno) -{ - struct disk_part_tbl *ptbl = rcu_dereference(disk->part_tbl); - - if (unlikely(partno < 0 || partno >= ptbl->len)) - return NULL; - return rcu_dereference(ptbl->part[partno]); -} - /** * disk_part_iter_init - initialize partition iterator * @piter: iterator to initialize @@ -185,26 +176,14 @@ struct block_device *__disk_get_part(struct gendisk *disk, int partno) void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk, unsigned int flags) { - struct disk_part_tbl *ptbl; - - rcu_read_lock(); - ptbl = rcu_dereference(disk->part_tbl); - piter->disk = disk; piter->part = NULL; - - if (flags & DISK_PITER_REVERSE) - piter->idx = ptbl->len - 1; - else if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0)) + if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0)) piter->idx = 0; else piter->idx = 1; - piter->flags = flags; - - rcu_read_unlock(); } -EXPORT_SYMBOL_GPL(disk_part_iter_init); /** * disk_part_iter_next - proceed iterator to the next partition and return it @@ -217,57 +196,30 @@ EXPORT_SYMBOL_GPL(disk_part_iter_init); */ struct block_device *disk_part_iter_next(struct disk_part_iter *piter) { - struct disk_part_tbl *ptbl; - int inc, end; + struct block_device *part; + unsigned long idx; /* put the last partition */ disk_part_iter_exit(piter); - /* get part_tbl */ rcu_read_lock(); - ptbl = rcu_dereference(piter->disk->part_tbl); - - /* determine iteration parameters */ - if (piter->flags & DISK_PITER_REVERSE) { - inc = -1; - if (piter->flags & (DISK_PITER_INCL_PART0 | - DISK_PITER_INCL_EMPTY_PART0)) - end = -1; - else - end = 0; - } else { - inc = 1; - end = ptbl->len; - } - - /* iterate to the next partition */ - for (; piter->idx != end; piter->idx += inc) { - struct block_device *part; - - part = rcu_dereference(ptbl->part[piter->idx]); - if (!part) - continue; - piter->part = bdgrab(part); - if (!piter->part) - continue; + xa_for_each_start(&piter->disk->part_tbl, idx, part, piter->idx) { if (!bdev_nr_sectors(part) && !(piter->flags & DISK_PITER_INCL_EMPTY) && !(piter->flags & DISK_PITER_INCL_EMPTY_PART0 && - piter->idx == 0)) { - bdput(piter->part); - piter->part = NULL; + piter->idx == 0)) continue; - } - piter->idx += inc; + piter->part = bdgrab(part); + if (!piter->part) + continue; + piter->idx = idx + 1; break; } - rcu_read_unlock(); return piter->part; } -EXPORT_SYMBOL_GPL(disk_part_iter_next); /** * disk_part_iter_exit - finish up partition iteration @@ -284,91 +236,6 @@ void disk_part_iter_exit(struct disk_part_iter *piter) bdput(piter->part); piter->part = NULL; } -EXPORT_SYMBOL_GPL(disk_part_iter_exit); - -static inline int sector_in_part(struct block_device *part, sector_t sector) -{ - return part->bd_start_sect <= sector && - sector < part->bd_start_sect + bdev_nr_sectors(part); -} - -/** - * disk_map_sector_rcu - map sector to partition - * @disk: gendisk of interest - * @sector: sector to map - * - * Find out which partition @sector maps to on @disk. This is - * primarily used for stats accounting. - * - * CONTEXT: - * RCU read locked. - * - * RETURNS: - * Found partition on success, part0 is returned if no partition matches - * or the matched partition is being deleted. - */ -struct block_device *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) -{ - struct disk_part_tbl *ptbl; - struct block_device *part; - int i; - - rcu_read_lock(); - ptbl = rcu_dereference(disk->part_tbl); - - part = rcu_dereference(ptbl->last_lookup); - if (part && sector_in_part(part, sector)) - goto out_unlock; - - for (i = 1; i < ptbl->len; i++) { - part = rcu_dereference(ptbl->part[i]); - if (part && sector_in_part(part, sector)) { - rcu_assign_pointer(ptbl->last_lookup, part); - goto out_unlock; - } - } - - part = disk->part0; -out_unlock: - rcu_read_unlock(); - return part; -} - -/** - * disk_has_partitions - * @disk: gendisk of interest - * - * Walk through the partition table and check if valid partition exists. - * - * CONTEXT: - * Don't care. - * - * RETURNS: - * True if the gendisk has at least one valid non-zero size partition. - * Otherwise false. - */ -bool disk_has_partitions(struct gendisk *disk) -{ - struct disk_part_tbl *ptbl; - int i; - bool ret = false; - - rcu_read_lock(); - ptbl = rcu_dereference(disk->part_tbl); - - /* Iterate partitions skipping the whole device at index 0 */ - for (i = 1; i < ptbl->len; i++) { - if (rcu_dereference(ptbl->part[i])) { - ret = true; - break; - } - } - - rcu_read_unlock(); - - return ret; -} -EXPORT_SYMBOL_GPL(disk_has_partitions); /* * Can be deleted altogether. Later. @@ -604,6 +471,18 @@ static char *bdevt_str(dev_t devt, char *buf) return buf; } +void disk_uevent(struct gendisk *disk, enum kobject_action action) +{ + struct disk_part_iter piter; + struct block_device *part; + + disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0); + while ((part = disk_part_iter_next(&piter))) + kobject_uevent(bdev_kobj(part), action); + disk_part_iter_exit(&piter); +} +EXPORT_SYMBOL_GPL(disk_uevent); + static void disk_scan_partitions(struct gendisk *disk) { struct block_device *bdev; @@ -621,8 +500,6 @@ static void register_disk(struct device *parent, struct gendisk *disk, const struct attribute_group **groups) { struct device *ddev = disk_to_dev(disk); - struct disk_part_iter piter; - struct block_device *part; int err; ddev->parent = parent; @@ -665,15 +542,9 @@ static void register_disk(struct device *parent, struct gendisk *disk, disk_scan_partitions(disk); - /* announce disk after possible partitions are created */ + /* announce the disk and partitions after all partitions are created */ dev_set_uevent_suppress(ddev, 0); - kobject_uevent(&ddev->kobj, KOBJ_ADD); - - /* announce possible partitions */ - disk_part_iter_init(&piter, disk, 0); - while ((part = disk_part_iter_next(&piter))) - kobject_uevent(bdev_kobj(part), KOBJ_ADD); - disk_part_iter_exit(&piter); + disk_uevent(disk, KOBJ_ADD); if (disk->queue->backing_dev_info->dev) { err = sysfs_create_link(&ddev->kobj, @@ -829,8 +700,7 @@ void del_gendisk(struct gendisk *disk) down_write(&bdev_lookup_sem); /* invalidate stuff */ - disk_part_iter_init(&piter, disk, - DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE); + disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); while ((part = disk_part_iter_next(&piter))) { invalidate_partition(part); delete_partition(part); @@ -929,7 +799,7 @@ struct block_device *bdget_disk(struct gendisk *disk, int partno) struct block_device *bdev = NULL; rcu_read_lock(); - bdev = __disk_get_part(disk, partno); + bdev = xa_load(&disk->part_tbl, partno); if (bdev && !bdgrab(bdev)) bdev = NULL; rcu_read_unlock(); @@ -1320,83 +1190,6 @@ static const struct attribute_group *disk_attr_groups[] = { }; /** - * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way - * @disk: disk to replace part_tbl for - * @new_ptbl: new part_tbl to install - * - * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The - * original ptbl is freed using RCU callback. - * - * LOCKING: - * Matching bd_mutex locked or the caller is the only user of @disk. - */ -static void disk_replace_part_tbl(struct gendisk *disk, - struct disk_part_tbl *new_ptbl) -{ - struct disk_part_tbl *old_ptbl = - rcu_dereference_protected(disk->part_tbl, 1); - - rcu_assign_pointer(disk->part_tbl, new_ptbl); - - if (old_ptbl) { - rcu_assign_pointer(old_ptbl->last_lookup, NULL); - kfree_rcu(old_ptbl, rcu_head); - } -} - -/** - * disk_expand_part_tbl - expand disk->part_tbl - * @disk: disk to expand part_tbl for - * @partno: expand such that this partno can fit in - * - * Expand disk->part_tbl such that @partno can fit in. disk->part_tbl - * uses RCU to allow unlocked dereferencing for stats and other stuff. - * - * LOCKING: - * Matching bd_mutex locked or the caller is the only user of @disk. - * Might sleep. - * - * RETURNS: - * 0 on success, -errno on failure. - */ -int disk_expand_part_tbl(struct gendisk *disk, int partno) -{ - struct disk_part_tbl *old_ptbl = - rcu_dereference_protected(disk->part_tbl, 1); - struct disk_part_tbl *new_ptbl; - int len = old_ptbl ? old_ptbl->len : 0; - int i, target; - - /* - * check for int overflow, since we can get here from blkpg_ioctl() - * with a user passed 'partno'. - */ - target = partno + 1; - if (target < 0) - return -EINVAL; - - /* disk_max_parts() is zero during initialization, ignore if so */ - if (disk_max_parts(disk) && target > disk_max_parts(disk)) - return -EINVAL; - - if (target <= len) - return 0; - - new_ptbl = kzalloc_node(struct_size(new_ptbl, part, target), GFP_KERNEL, - disk->node_id); - if (!new_ptbl) - return -ENOMEM; - - new_ptbl->len = target; - - for (i = 0; i < len; i++) - rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]); - - disk_replace_part_tbl(disk, new_ptbl); - return 0; -} - -/** * disk_release - releases all allocated resources of the gendisk * @dev: the device representing this disk * @@ -1419,7 +1212,7 @@ static void disk_release(struct device *dev) blk_free_devt(dev->devt); disk_release_events(disk); kfree(disk->random); - disk_replace_part_tbl(disk, NULL); + xa_destroy(&disk->part_tbl); bdput(disk->part0); if (disk->queue) blk_put_queue(disk->queue); @@ -1572,7 +1365,6 @@ dev_t blk_lookup_devt(const char *name, int partno) struct gendisk *__alloc_disk_node(int minors, int node_id) { struct gendisk *disk; - struct disk_part_tbl *ptbl; if (minors > DISK_MAX_PARTS) { printk(KERN_ERR @@ -1590,11 +1382,9 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) goto out_free_disk; disk->node_id = node_id; - if (disk_expand_part_tbl(disk, 0)) - goto out_bdput; - - ptbl = rcu_dereference_protected(disk->part_tbl, 1); - rcu_assign_pointer(ptbl->part[0], disk->part0); + xa_init(&disk->part_tbl); + if (xa_insert(&disk->part_tbl, 0, disk->part0, GFP_KERNEL)) + goto out_destroy_part_tbl; disk->minors = minors; rand_initialize_disk(disk); @@ -1603,7 +1393,8 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) device_initialize(disk_to_dev(disk)); return disk; -out_bdput: +out_destroy_part_tbl: + xa_destroy(&disk->part_tbl); bdput(disk->part0); out_free_disk: kfree(disk); @@ -1638,31 +1429,32 @@ static void set_disk_ro_uevent(struct gendisk *gd, int ro) kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp); } -void set_disk_ro(struct gendisk *disk, int flag) +/** + * set_disk_ro - set a gendisk read-only + * @disk: gendisk to operate on + * @read_only: %true to set the disk read-only, %false set the disk read/write + * + * This function is used to indicate whether a given disk device should have its + * read-only flag set. set_disk_ro() is typically used by device drivers to + * indicate whether the underlying physical device is write-protected. + */ +void set_disk_ro(struct gendisk *disk, bool read_only) { - struct disk_part_iter piter; - struct block_device *part; - - if (disk->part0->bd_read_only != flag) { - set_disk_ro_uevent(disk, flag); - disk->part0->bd_read_only = flag; + if (read_only) { + if (test_and_set_bit(GD_READ_ONLY, &disk->state)) + return; + } else { + if (!test_and_clear_bit(GD_READ_ONLY, &disk->state)) + return; } - - disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); - while ((part = disk_part_iter_next(&piter))) - part->bd_read_only = flag; - disk_part_iter_exit(&piter); + set_disk_ro_uevent(disk, read_only); } - EXPORT_SYMBOL(set_disk_ro); int bdev_read_only(struct block_device *bdev) { - if (!bdev) - return 0; - return bdev->bd_read_only; + return bdev->bd_read_only || get_disk_ro(bdev->bd_disk); } - EXPORT_SYMBOL(bdev_read_only); /* |