diff options
Diffstat (limited to 'block/genhd.c')
| -rw-r--r-- | block/genhd.c | 2230 |
1 files changed, 809 insertions, 1421 deletions
diff --git a/block/genhd.c b/block/genhd.c index 26b31fcae217..d74fb5b4ae68 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -1,11 +1,13 @@ // SPDX-License-Identifier: GPL-2.0 /* * gendisk handling + * + * Portions Copyright (C) 2020 Christoph Hellwig */ #include <linux/module.h> +#include <linux/ctype.h> #include <linux/fs.h> -#include <linux/genhd.h> #include <linux/kdev_t.h> #include <linux/kernel.h> #include <linux/blkdev.h> @@ -16,66 +18,111 @@ #include <linux/seq_file.h> #include <linux/slab.h> #include <linux/kmod.h> -#include <linux/kobj_map.h> +#include <linux/major.h> #include <linux/mutex.h> #include <linux/idr.h> #include <linux/log2.h> #include <linux/pm_runtime.h> #include <linux/badblocks.h> +#include <linux/part_stat.h> +#include <linux/blktrace_api.h> +#include "blk-throttle.h" #include "blk.h" +#include "blk-mq-sched.h" +#include "blk-rq-qos.h" +#include "blk-cgroup.h" + +static struct kobject *block_depr; -static DEFINE_MUTEX(block_class_lock); -struct kobject *block_depr; +/* + * Unique, monotonically increasing sequential number associated with block + * devices instances (i.e. incremented each time a device is attached). + * Associating uevents with block devices in userspace is difficult and racy: + * the uevent netlink socket is lossy, and on slow and overloaded systems has + * a very high latency. + * Block devices do not have exclusive owners in userspace, any process can set + * one up (e.g. loop devices). Moreover, device names can be reused (e.g. loop0 + * can be reused again and again). + * A userspace process setting up a block device and watching for its events + * cannot thus reliably tell whether an event relates to the device it just set + * up or another earlier instance with the same name. + * This sequential number allows userspace processes to solve this problem, and + * uniquely associate an uevent to the lifetime to a device. + */ +static atomic64_t diskseq; /* for extended dynamic devt allocation, currently only one major is used */ #define NR_EXT_DEVT (1 << MINORBITS) +static DEFINE_IDA(ext_devt_ida); -/* For extended devt allocation. ext_devt_lock prevents look up - * results from going away underneath its user. +void set_capacity(struct gendisk *disk, sector_t sectors) +{ + bdev_set_nr_sectors(disk->part0, sectors); +} +EXPORT_SYMBOL(set_capacity); + +/* + * Set disk capacity and notify if the size is not currently zero and will not + * be set to zero. Returns true if a uevent was sent, otherwise false. */ -static DEFINE_SPINLOCK(ext_devt_lock); -static DEFINE_IDR(ext_devt_idr); +bool set_capacity_and_notify(struct gendisk *disk, sector_t size) +{ + sector_t capacity = get_capacity(disk); + char *envp[] = { "RESIZE=1", NULL }; -static const struct device_type disk_type; + set_capacity(disk, size); -static void disk_check_events(struct disk_events *ev, - unsigned int *clearing_ptr); -static void disk_alloc_events(struct gendisk *disk); -static void disk_add_events(struct gendisk *disk); -static void disk_del_events(struct gendisk *disk); -static void disk_release_events(struct gendisk *disk); + /* + * Only print a message and send a uevent if the gendisk is user visible + * and alive. This avoids spamming the log and udev when setting the + * initial capacity during probing. + */ + if (size == capacity || + !disk_live(disk) || + (disk->flags & GENHD_FL_HIDDEN)) + return false; -void part_inc_in_flight(struct request_queue *q, struct hd_struct *part, int rw) -{ - if (queue_is_mq(q)) - return; + pr_info("%s: detected capacity change from %lld to %lld\n", + disk->disk_name, capacity, size); - part_stat_local_inc(part, in_flight[rw]); - if (part->partno) - part_stat_local_inc(&part_to_disk(part)->part0, in_flight[rw]); + /* + * Historically we did not send a uevent for changes to/from an empty + * device. + */ + if (!capacity || !size) + return false; + kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp); + return true; } +EXPORT_SYMBOL_GPL(set_capacity_and_notify); -void part_dec_in_flight(struct request_queue *q, struct hd_struct *part, int rw) +static void part_stat_read_all(struct block_device *part, + struct disk_stats *stat) { - if (queue_is_mq(q)) - return; + int cpu; + + memset(stat, 0, sizeof(struct disk_stats)); + for_each_possible_cpu(cpu) { + struct disk_stats *ptr = per_cpu_ptr(part->bd_stats, cpu); + int group; + + for (group = 0; group < NR_STAT_GROUPS; group++) { + stat->nsecs[group] += ptr->nsecs[group]; + stat->sectors[group] += ptr->sectors[group]; + stat->ios[group] += ptr->ios[group]; + stat->merges[group] += ptr->merges[group]; + } - part_stat_local_dec(part, in_flight[rw]); - if (part->partno) - part_stat_local_dec(&part_to_disk(part)->part0, in_flight[rw]); + stat->io_ticks += ptr->io_ticks; + } } -unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part) +static unsigned int part_in_flight(struct block_device *part) { + unsigned int inflight = 0; int cpu; - unsigned int inflight; - - if (queue_is_mq(q)) { - return blk_mq_in_flight(q, part); - } - inflight = 0; for_each_possible_cpu(cpu) { inflight += part_stat_local_read_cpu(part, in_flight[0], cpu) + part_stat_local_read_cpu(part, in_flight[1], cpu); @@ -86,16 +133,11 @@ unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part) return inflight; } -void part_in_flight_rw(struct request_queue *q, struct hd_struct *part, - unsigned int inflight[2]) +static void part_in_flight_rw(struct block_device *part, + unsigned int inflight[2]) { int cpu; - if (queue_is_mq(q)) { - blk_mq_in_flight_rw(q, part, inflight); - return; - } - inflight[0] = 0; inflight[1] = 0; for_each_possible_cpu(cpu) { @@ -108,199 +150,6 @@ void part_in_flight_rw(struct request_queue *q, struct hd_struct *part, inflight[1] = 0; } -struct hd_struct *__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_get_part - get partition - * @disk: disk to look partition from - * @partno: partition number - * - * Look for partition @partno from @disk. If found, increment - * reference count and return it. - * - * CONTEXT: - * Don't care. - * - * RETURNS: - * Pointer to the found partition on success, NULL if not found. - */ -struct hd_struct *disk_get_part(struct gendisk *disk, int partno) -{ - struct hd_struct *part; - - rcu_read_lock(); - part = __disk_get_part(disk, partno); - if (part) - get_device(part_to_dev(part)); - rcu_read_unlock(); - - return part; -} -EXPORT_SYMBOL_GPL(disk_get_part); - -/** - * disk_part_iter_init - initialize partition iterator - * @piter: iterator to initialize - * @disk: disk to iterate over - * @flags: DISK_PITER_* flags - * - * Initialize @piter so that it iterates over partitions of @disk. - * - * CONTEXT: - * Don't care. - */ -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)) - 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 - * @piter: iterator of interest - * - * Proceed @piter to the next partition and return it. - * - * CONTEXT: - * Don't care. - */ -struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter) -{ - struct disk_part_tbl *ptbl; - int inc, end; - - /* put the last partition */ - disk_put_part(piter->part); - piter->part = NULL; - - /* 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 hd_struct *part; - - part = rcu_dereference(ptbl->part[piter->idx]); - if (!part) - continue; - if (!part_nr_sects_read(part) && - !(piter->flags & DISK_PITER_INCL_EMPTY) && - !(piter->flags & DISK_PITER_INCL_EMPTY_PART0 && - piter->idx == 0)) - continue; - - get_device(part_to_dev(part)); - piter->part = part; - piter->idx += inc; - break; - } - - rcu_read_unlock(); - - return piter->part; -} -EXPORT_SYMBOL_GPL(disk_part_iter_next); - -/** - * disk_part_iter_exit - finish up partition iteration - * @piter: iter of interest - * - * Called when iteration is over. Cleans up @piter. - * - * CONTEXT: - * Don't care. - */ -void disk_part_iter_exit(struct disk_part_iter *piter) -{ - disk_put_part(piter->part); - piter->part = NULL; -} -EXPORT_SYMBOL_GPL(disk_part_iter_exit); - -static inline int sector_in_part(struct hd_struct *part, sector_t sector) -{ - return part->start_sect <= sector && - sector < part->start_sect + part_nr_sects_read(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. The returned partition pointer is valid only - * while preemption is disabled. - * - * RETURNS: - * Found partition on success, part0 is returned if no partition matches - */ -struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) -{ - struct disk_part_tbl *ptbl; - struct hd_struct *part; - int i; - - ptbl = rcu_dereference(disk->part_tbl); - - part = rcu_dereference(ptbl->last_lookup); - if (part && sector_in_part(part, sector)) - return part; - - 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); - return part; - } - } - return &disk->part0; -} -EXPORT_SYMBOL_GPL(disk_map_sector_rcu); - /* * Can be deleted altogether. Later. * @@ -310,7 +159,12 @@ static struct blk_major_name { struct blk_major_name *next; int major; char name[16]; +#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD + void (*probe)(dev_t devt); +#endif } *major_names[BLKDEV_MAJOR_HASH_SIZE]; +static DEFINE_MUTEX(major_names_lock); +static DEFINE_SPINLOCK(major_names_spinlock); /* index in the above - for now: assume no multimajor ranges */ static inline int major_to_index(unsigned major) @@ -323,20 +177,24 @@ void blkdev_show(struct seq_file *seqf, off_t offset) { struct blk_major_name *dp; - mutex_lock(&block_class_lock); + spin_lock(&major_names_spinlock); for (dp = major_names[major_to_index(offset)]; dp; dp = dp->next) if (dp->major == offset) seq_printf(seqf, "%3d %s\n", dp->major, dp->name); - mutex_unlock(&block_class_lock); + spin_unlock(&major_names_spinlock); } #endif /* CONFIG_PROC_FS */ /** - * register_blkdev - register a new block device + * __register_blkdev - register a new block device * * @major: the requested major device number [1..BLKDEV_MAJOR_MAX-1]. If * @major = 0, try to allocate any unused major number. * @name: the name of the new block device as a zero terminated string + * @probe: pre-devtmpfs / pre-udev callback used to create disks when their + * pre-created device node is accessed. When a probe call uses + * add_disk() and it fails the driver must cleanup resources. This + * interface may soon be removed. * * The @name must be unique within the system. * @@ -350,13 +208,16 @@ void blkdev_show(struct seq_file *seqf, off_t offset) * * See Documentation/admin-guide/devices.txt for the list of allocated * major numbers. + * + * Use register_blkdev instead for any new code. */ -int register_blkdev(unsigned int major, const char *name) +int __register_blkdev(unsigned int major, const char *name, + void (*probe)(dev_t devt)) { struct blk_major_name **n, *p; int index, ret = 0; - mutex_lock(&block_class_lock); + mutex_lock(&major_names_lock); /* temporary */ if (major == 0) { @@ -390,10 +251,14 @@ int register_blkdev(unsigned int major, const char *name) } p->major = major; - strlcpy(p->name, name, sizeof(p->name)); +#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD + p->probe = probe; +#endif + strscpy(p->name, name, sizeof(p->name)); p->next = NULL; index = major_to_index(major); + spin_lock(&major_names_spinlock); for (n = &major_names[index]; *n; n = &(*n)->next) { if ((*n)->major == major) break; @@ -402,6 +267,7 @@ int register_blkdev(unsigned int major, const char *name) *n = p; else ret = -EBUSY; + spin_unlock(&major_names_spinlock); if (ret < 0) { printk("register_blkdev: cannot get major %u for %s\n", @@ -409,11 +275,10 @@ int register_blkdev(unsigned int major, const char *name) kfree(p); } out: - mutex_unlock(&block_class_lock); + mutex_unlock(&major_names_lock); return ret; } - -EXPORT_SYMBOL(register_blkdev); +EXPORT_SYMBOL(__register_blkdev); void unregister_blkdev(unsigned int major, const char *name) { @@ -421,7 +286,8 @@ void unregister_blkdev(unsigned int major, const char *name) struct blk_major_name *p = NULL; int index = major_to_index(major); - mutex_lock(&block_class_lock); + mutex_lock(&major_names_lock); + spin_lock(&major_names_spinlock); for (n = &major_names[index]; *n; n = &(*n)->next) if ((*n)->major == major) break; @@ -431,198 +297,176 @@ void unregister_blkdev(unsigned int major, const char *name) p = *n; *n = p->next; } - mutex_unlock(&block_class_lock); + spin_unlock(&major_names_spinlock); + mutex_unlock(&major_names_lock); kfree(p); } EXPORT_SYMBOL(unregister_blkdev); -static struct kobj_map *bdev_map; - -/** - * blk_mangle_minor - scatter minor numbers apart - * @minor: minor number to mangle - * - * Scatter consecutively allocated @minor number apart if MANGLE_DEVT - * is enabled. Mangling twice gives the original value. - * - * RETURNS: - * Mangled value. - * - * CONTEXT: - * Don't care. - */ -static int blk_mangle_minor(int minor) +int blk_alloc_ext_minor(void) { -#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT - int i; - - for (i = 0; i < MINORBITS / 2; i++) { - int low = minor & (1 << i); - int high = minor & (1 << (MINORBITS - 1 - i)); - int distance = MINORBITS - 1 - 2 * i; + int idx; - minor ^= low | high; /* clear both bits */ - low <<= distance; /* swap the positions */ - high >>= distance; - minor |= low | high; /* and set */ - } -#endif - return minor; + idx = ida_alloc_range(&ext_devt_ida, 0, NR_EXT_DEVT - 1, GFP_KERNEL); + if (idx == -ENOSPC) + return -EBUSY; + return idx; } -/** - * blk_alloc_devt - allocate a dev_t for a partition - * @part: partition to allocate dev_t for - * @devt: out parameter for resulting dev_t - * - * Allocate a dev_t for block device. - * - * RETURNS: - * 0 on success, allocated dev_t is returned in *@devt. -errno on - * failure. - * - * CONTEXT: - * Might sleep. - */ -int blk_alloc_devt(struct hd_struct *part, dev_t *devt) +void blk_free_ext_minor(unsigned int minor) { - struct gendisk *disk = part_to_disk(part); - int idx; - - /* in consecutive minor range? */ - if (part->partno < disk->minors) { - *devt = MKDEV(disk->major, disk->first_minor + part->partno); - return 0; - } - - /* allocate ext devt */ - idr_preload(GFP_KERNEL); - - spin_lock_bh(&ext_devt_lock); - idx = idr_alloc(&ext_devt_idr, part, 0, NR_EXT_DEVT, GFP_NOWAIT); - spin_unlock_bh(&ext_devt_lock); - - idr_preload_end(); - if (idx < 0) - return idx == -ENOSPC ? -EBUSY : idx; - - *devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx)); - return 0; + ida_free(&ext_devt_ida, minor); } -/** - * blk_free_devt - free a dev_t - * @devt: dev_t to free - * - * Free @devt which was allocated using blk_alloc_devt(). - * - * CONTEXT: - * Might sleep. - */ -void blk_free_devt(dev_t devt) +void disk_uevent(struct gendisk *disk, enum kobject_action action) { - if (devt == MKDEV(0, 0)) - return; + struct block_device *part; + unsigned long idx; - if (MAJOR(devt) == BLOCK_EXT_MAJOR) { - spin_lock_bh(&ext_devt_lock); - idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt))); - spin_unlock_bh(&ext_devt_lock); - } -} + rcu_read_lock(); + xa_for_each(&disk->part_tbl, idx, part) { + if (bdev_is_partition(part) && !bdev_nr_sectors(part)) + continue; + if (!kobject_get_unless_zero(&part->bd_device.kobj)) + continue; -/* - * We invalidate devt by assigning NULL pointer for devt in idr. - */ -void blk_invalidate_devt(dev_t devt) -{ - if (MAJOR(devt) == BLOCK_EXT_MAJOR) { - spin_lock_bh(&ext_devt_lock); - idr_replace(&ext_devt_idr, NULL, blk_mangle_minor(MINOR(devt))); - spin_unlock_bh(&ext_devt_lock); + rcu_read_unlock(); + kobject_uevent(bdev_kobj(part), action); + put_device(&part->bd_device); + rcu_read_lock(); } + rcu_read_unlock(); } +EXPORT_SYMBOL_GPL(disk_uevent); -static char *bdevt_str(dev_t devt, char *buf) +int disk_scan_partitions(struct gendisk *disk, blk_mode_t mode) { - if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) { - char tbuf[BDEVT_SIZE]; - snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt)); - snprintf(buf, BDEVT_SIZE, "%-9s", tbuf); - } else - snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt)); - - return buf; -} + struct bdev_handle *handle; + int ret = 0; -/* - * Register device numbers dev..(dev+range-1) - * range must be nonzero - * The hash chain is sorted on range, so that subranges can override. - */ -void blk_register_region(dev_t devt, unsigned long range, struct module *module, - struct kobject *(*probe)(dev_t, int *, void *), - int (*lock)(dev_t, void *), void *data) -{ - kobj_map(bdev_map, devt, range, module, probe, lock, data); -} + if (disk->flags & (GENHD_FL_NO_PART | GENHD_FL_HIDDEN)) + return -EINVAL; + if (test_bit(GD_SUPPRESS_PART_SCAN, &disk->state)) + return -EINVAL; + if (disk->open_partitions) + return -EBUSY; -EXPORT_SYMBOL(blk_register_region); + /* + * If the device is opened exclusively by current thread already, it's + * safe to scan partitons, otherwise, use bd_prepare_to_claim() to + * synchronize with other exclusive openers and other partition + * scanners. + */ + if (!(mode & BLK_OPEN_EXCL)) { + ret = bd_prepare_to_claim(disk->part0, disk_scan_partitions, + NULL); + if (ret) + return ret; + } -void blk_unregister_region(dev_t devt, unsigned long range) -{ - kobj_unmap(bdev_map, devt, range); + set_bit(GD_NEED_PART_SCAN, &disk->state); + handle = bdev_open_by_dev(disk_devt(disk), mode & ~BLK_OPEN_EXCL, NULL, + NULL); + if (IS_ERR(handle)) + ret = PTR_ERR(handle); + else + bdev_release(handle); + + /* + * If blkdev_get_by_dev() failed early, GD_NEED_PART_SCAN is still set, + * and this will cause that re-assemble partitioned raid device will + * creat partition for underlying disk. + */ + clear_bit(GD_NEED_PART_SCAN, &disk->state); + if (!(mode & BLK_OPEN_EXCL)) + bd_abort_claiming(disk->part0, disk_scan_partitions); + return ret; } -EXPORT_SYMBOL(blk_unregister_region); +/** + * device_add_disk - add disk information to kernel list + * @parent: parent device for the disk + * @disk: per-device partitioning information + * @groups: Additional per-device sysfs groups + * + * This function registers the partitioning information in @disk + * with the kernel. + */ +int __must_check device_add_disk(struct device *parent, struct gendisk *disk, + const struct attribute_group **groups) -static struct kobject *exact_match(dev_t devt, int *partno, void *data) { - struct gendisk *p = data; + struct device *ddev = disk_to_dev(disk); + int ret; - return &disk_to_dev(p)->kobj; -} + /* Only makes sense for bio-based to set ->poll_bio */ + if (queue_is_mq(disk->queue) && disk->fops->poll_bio) + return -EINVAL; -static int exact_lock(dev_t devt, void *data) -{ - struct gendisk *p = data; + /* + * The disk queue should now be all set with enough information about + * the device for the elevator code to pick an adequate default + * elevator if one is needed, that is, for devices requesting queue + * registration. + */ + elevator_init_mq(disk->queue); - if (!get_disk_and_module(p)) - return -1; - return 0; -} + /* Mark bdev as having a submit_bio, if needed */ + disk->part0->bd_has_submit_bio = disk->fops->submit_bio != NULL; -static void register_disk(struct device *parent, struct gendisk *disk, - const struct attribute_group **groups) -{ - struct device *ddev = disk_to_dev(disk); - struct block_device *bdev; - struct disk_part_iter piter; - struct hd_struct *part; - int err; + /* + * If the driver provides an explicit major number it also must provide + * the number of minors numbers supported, and those will be used to + * setup the gendisk. + * Otherwise just allocate the device numbers for both the whole device + * and all partitions from the extended dev_t space. + */ + ret = -EINVAL; + if (disk->major) { + if (WARN_ON(!disk->minors)) + goto out_exit_elevator; + + if (disk->minors > DISK_MAX_PARTS) { + pr_err("block: can't allocate more than %d partitions\n", + DISK_MAX_PARTS); + disk->minors = DISK_MAX_PARTS; + } + if (disk->first_minor > MINORMASK || + disk->minors > MINORMASK + 1 || + disk->first_minor + disk->minors > MINORMASK + 1) + goto out_exit_elevator; + } else { + if (WARN_ON(disk->minors)) + goto out_exit_elevator; + + ret = blk_alloc_ext_minor(); + if (ret < 0) + goto out_exit_elevator; + disk->major = BLOCK_EXT_MAJOR; + disk->first_minor = ret; + } - ddev->parent = parent; + /* delay uevents, until we scanned partition table */ + dev_set_uevent_suppress(ddev, 1); + ddev->parent = parent; + ddev->groups = groups; dev_set_name(ddev, "%s", disk->disk_name); + if (!(disk->flags & GENHD_FL_HIDDEN)) + ddev->devt = MKDEV(disk->major, disk->first_minor); + ret = device_add(ddev); + if (ret) + goto out_free_ext_minor; - /* delay uevents, until we scanned partition table */ - dev_set_uevent_suppress(ddev, 1); + ret = disk_alloc_events(disk); + if (ret) + goto out_device_del; - if (groups) { - WARN_ON(ddev->groups); - ddev->groups = groups; - } - if (device_add(ddev)) - return; - if (!sysfs_deprecated) { - err = sysfs_create_link(block_depr, &ddev->kobj, - kobject_name(&ddev->kobj)); - if (err) { - device_del(ddev); - return; - } - } + ret = sysfs_create_link(block_depr, &ddev->kobj, + kobject_name(&ddev->kobj)); + if (ret) + goto out_device_del; /* * avoid probable deadlock caused by allocating memory with @@ -631,210 +475,281 @@ static void register_disk(struct device *parent, struct gendisk *disk, */ pm_runtime_set_memalloc_noio(ddev, true); - disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj); + disk->part0->bd_holder_dir = + kobject_create_and_add("holders", &ddev->kobj); + if (!disk->part0->bd_holder_dir) { + ret = -ENOMEM; + goto out_del_block_link; + } disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj); + if (!disk->slave_dir) { + ret = -ENOMEM; + goto out_put_holder_dir; + } + + ret = blk_register_queue(disk); + if (ret) + goto out_put_slave_dir; + + if (!(disk->flags & GENHD_FL_HIDDEN)) { + ret = bdi_register(disk->bdi, "%u:%u", + disk->major, disk->first_minor); + if (ret) + goto out_unregister_queue; + bdi_set_owner(disk->bdi, ddev); + ret = sysfs_create_link(&ddev->kobj, + &disk->bdi->dev->kobj, "bdi"); + if (ret) + goto out_unregister_bdi; + + /* Make sure the first partition scan will be proceed */ + if (get_capacity(disk) && !(disk->flags & GENHD_FL_NO_PART) && + !test_bit(GD_SUPPRESS_PART_SCAN, &disk->state)) + set_bit(GD_NEED_PART_SCAN, &disk->state); + + bdev_add(disk->part0, ddev->devt); + if (get_capacity(disk)) + disk_scan_partitions(disk, BLK_OPEN_READ); - if (disk->flags & GENHD_FL_HIDDEN) { + /* + * Announce the disk and partitions after all partitions are + * created. (for hidden disks uevents remain suppressed forever) + */ dev_set_uevent_suppress(ddev, 0); - return; + disk_uevent(disk, KOBJ_ADD); + } else { + /* + * Even if the block_device for a hidden gendisk is not + * registered, it needs to have a valid bd_dev so that the + * freeing of the dynamic major works. + */ + disk->part0->bd_dev = MKDEV(disk->major, disk->first_minor); } - /* No minors to use for partitions */ - if (!disk_part_scan_enabled(disk)) - goto exit; - - /* No such device (e.g., media were just removed) */ - if (!get_capacity(disk)) - goto exit; - - bdev = bdget_disk(disk, 0); - if (!bdev) - goto exit; - - bdev->bd_invalidated = 1; - err = blkdev_get(bdev, FMODE_READ, NULL); - if (err < 0) - goto exit; - blkdev_put(bdev, FMODE_READ); - -exit: - /* announce disk after possible 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(&part_to_dev(part)->kobj, KOBJ_ADD); - disk_part_iter_exit(&piter); - - if (disk->queue->backing_dev_info->dev) { - err = sysfs_create_link(&ddev->kobj, - &disk->queue->backing_dev_info->dev->kobj, - "bdi"); - WARN_ON(err); - } + disk_update_readahead(disk); + disk_add_events(disk); + set_bit(GD_ADDED, &disk->state); + return 0; + +out_unregister_bdi: + if (!(disk->flags & GENHD_FL_HIDDEN)) + bdi_unregister(disk->bdi); +out_unregister_queue: + blk_unregister_queue(disk); + rq_qos_exit(disk->queue); +out_put_slave_dir: + kobject_put(disk->slave_dir); + disk->slave_dir = NULL; +out_put_holder_dir: + kobject_put(disk->part0->bd_holder_dir); +out_del_block_link: + sysfs_remove_link(block_depr, dev_name(ddev)); + pm_runtime_set_memalloc_noio(ddev, false); +out_device_del: + device_del(ddev); +out_free_ext_minor: + if (disk->major == BLOCK_EXT_MAJOR) + blk_free_ext_minor(disk->first_minor); +out_exit_elevator: + if (disk->queue->elevator) + elevator_exit(disk->queue); + return ret; } +EXPORT_SYMBOL(device_add_disk); -/** - * __device_add_disk - add disk information to kernel list - * @parent: parent device for the disk - * @disk: per-device partitioning information - * @groups: Additional per-device sysfs groups - * @register_queue: register the queue if set to true - * - * This function registers the partitioning information in @disk - * with the kernel. - * - * FIXME: error handling - */ -static void __device_add_disk(struct device *parent, struct gendisk *disk, - const struct attribute_group **groups, - bool register_queue) +static void blk_report_disk_dead(struct gendisk *disk, bool surprise) { - dev_t devt; - int retval; + struct block_device *bdev; + unsigned long idx; /* - * The disk queue should now be all set with enough information about - * the device for the elevator code to pick an adequate default - * elevator if one is needed, that is, for devices requesting queue - * registration. - */ - if (register_queue) - elevator_init_mq(disk->queue); - - /* minors == 0 indicates to use ext devt from part0 and should - * be accompanied with EXT_DEVT flag. Make sure all - * parameters make sense. + * On surprise disk removal, bdev_mark_dead() may call into file + * systems below. Make it clear that we're expecting to not hold + * disk->open_mutex. */ - WARN_ON(disk->minors && !(disk->major || disk->first_minor)); - WARN_ON(!disk->minors && - !(disk->flags & (GENHD_FL_EXT_DEVT | GENHD_FL_HIDDEN))); + lockdep_assert_not_held(&disk->open_mutex); - disk->flags |= GENHD_FL_UP; - - retval = blk_alloc_devt(&disk->part0, &devt); - if (retval) { - WARN_ON(1); - return; - } - disk->major = MAJOR(devt); - disk->first_minor = MINOR(devt); + rcu_read_lock(); + xa_for_each(&disk->part_tbl, idx, bdev) { + if (!kobject_get_unless_zero(&bdev->bd_device.kobj)) + continue; + rcu_read_unlock(); - disk_alloc_events(disk); + bdev_mark_dead(bdev, surprise); - 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 { - int ret; - - /* Register BDI before referencing it from bdev */ - disk_to_dev(disk)->devt = devt; - ret = bdi_register_owner(disk->queue->backing_dev_info, - disk_to_dev(disk)); - WARN_ON(ret); - blk_register_region(disk_devt(disk), disk->minors, NULL, - exact_match, exact_lock, disk); + put_device(&bdev->bd_device); + rcu_read_lock(); } - register_disk(parent, disk, groups); - if (register_queue) - blk_register_queue(disk); + rcu_read_unlock(); +} +static void __blk_mark_disk_dead(struct gendisk *disk) +{ /* - * Take an extra ref on queue which will be put on disk_release() - * so that it sticks around as long as @disk is there. + * Fail any new I/O. */ - WARN_ON_ONCE(!blk_get_queue(disk->queue)); + if (test_and_set_bit(GD_DEAD, &disk->state)) + return; - disk_add_events(disk); - blk_integrity_add(disk); -} + if (test_bit(GD_OWNS_QUEUE, &disk->state)) + blk_queue_flag_set(QUEUE_FLAG_DYING, disk->queue); -void device_add_disk(struct device *parent, struct gendisk *disk, - const struct attribute_group **groups) + /* + * Stop buffered writers from dirtying pages that can't be written out. + */ + set_capacity(disk, 0); -{ - __device_add_disk(parent, disk, groups, true); + /* + * Prevent new I/O from crossing bio_queue_enter(). + */ + blk_queue_start_drain(disk->queue); } -EXPORT_SYMBOL(device_add_disk); -void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk) +/** + * blk_mark_disk_dead - mark a disk as dead + * @disk: disk to mark as dead + * + * Mark as disk as dead (e.g. surprise removed) and don't accept any new I/O + * to this disk. + */ +void blk_mark_disk_dead(struct gendisk *disk) { - __device_add_disk(parent, disk, NULL, false); + __blk_mark_disk_dead(disk); + blk_report_disk_dead(disk, true); } -EXPORT_SYMBOL(device_add_disk_no_queue_reg); +EXPORT_SYMBOL_GPL(blk_mark_disk_dead); +/** + * del_gendisk - remove the gendisk + * @disk: the struct gendisk to remove + * + * Removes the gendisk and all its associated resources. This deletes the + * partitions associated with the gendisk, and unregisters the associated + * request_queue. + * + * This is the counter to the respective __device_add_disk() call. + * + * The final removal of the struct gendisk happens when its refcount reaches 0 + * with put_disk(), which should be called after del_gendisk(), if + * __device_add_disk() was used. + * + * Drivers exist which depend on the release of the gendisk to be synchronous, + * it should not be deferred. + * + * Context: can sleep + */ void del_gendisk(struct gendisk *disk) { - struct disk_part_iter piter; - struct hd_struct *part; + struct request_queue *q = disk->queue; + struct block_device *part; + unsigned long idx; + + might_sleep(); + + if (WARN_ON_ONCE(!disk_live(disk) && !(disk->flags & GENHD_FL_HIDDEN))) + return; - blk_integrity_del(disk); disk_del_events(disk); /* - * Block lookups of the disk until all bdevs are unhashed and the - * disk is marked as dead (GENHD_FL_UP cleared). + * Prevent new openers by unlinked the bdev inode. */ - down_write(&disk->lookup_sem); - /* invalidate stuff */ - disk_part_iter_init(&piter, disk, - DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE); - while ((part = disk_part_iter_next(&piter))) { - invalidate_partition(disk, part->partno); - bdev_unhash_inode(part_devt(part)); - delete_partition(disk, part->partno); - } - disk_part_iter_exit(&piter); + mutex_lock(&disk->open_mutex); + xa_for_each(&disk->part_tbl, idx, part) + remove_inode_hash(part->bd_inode); + mutex_unlock(&disk->open_mutex); - invalidate_partition(disk, 0); - bdev_unhash_inode(disk_devt(disk)); - set_capacity(disk, 0); - disk->flags &= ~GENHD_FL_UP; - up_write(&disk->lookup_sem); + /* + * Tell the file system to write back all dirty data and shut down if + * it hasn't been notified earlier. + */ + if (!test_bit(GD_DEAD, &disk->state)) + blk_report_disk_dead(disk, false); + __blk_mark_disk_dead(disk); - if (!(disk->flags & GENHD_FL_HIDDEN)) + /* + * Drop all partitions now that the disk is marked dead. + */ + mutex_lock(&disk->open_mutex); + xa_for_each_start(&disk->part_tbl, idx, part, 1) + drop_partition(part); + mutex_unlock(&disk->open_mutex); + + 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 * get reused and we'd get clashes in sysfs). */ - if (!(disk->flags & GENHD_FL_HIDDEN)) - bdi_unregister(disk->queue->backing_dev_info); - blk_unregister_queue(disk); - } else { - WARN_ON(1); + bdi_unregister(disk->bdi); } - if (!(disk->flags & GENHD_FL_HIDDEN)) - blk_unregister_region(disk_devt(disk), disk->minors); - /* - * Remove gendisk pointer from idr so that it cannot be looked up - * while RCU period before freeing gendisk is running to prevent - * use-after-free issues. Note that the device number stays - * "in-use" until we really free the gendisk. - */ - blk_invalidate_devt(disk_devt(disk)); + blk_unregister_queue(disk); - kobject_put(disk->part0.holder_dir); + kobject_put(disk->part0->bd_holder_dir); kobject_put(disk->slave_dir); + disk->slave_dir = NULL; - part_stat_set_all(&disk->part0, 0); - disk->part0.stamp = 0; - if (!sysfs_deprecated) - sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk))); + part_stat_set_all(disk->part0, 0); + disk->part0->bd_stamp = 0; + sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk))); pm_runtime_set_memalloc_noio(disk_to_dev(disk), false); device_del(disk_to_dev(disk)); + + blk_mq_freeze_queue_wait(q); + + blk_throtl_cancel_bios(disk); + + blk_sync_queue(q); + blk_flush_integrity(); + + if (queue_is_mq(q)) + blk_mq_cancel_work_sync(q); + + blk_mq_quiesce_queue(q); + if (q->elevator) { + mutex_lock(&q->sysfs_lock); + elevator_exit(q); + mutex_unlock(&q->sysfs_lock); + } + rq_qos_exit(q); + blk_mq_unquiesce_queue(q); + + /* + * If the disk does not own the queue, allow using passthrough requests + * again. Else leave the queue frozen to fail all I/O. + */ + if (!test_bit(GD_OWNS_QUEUE, &disk->state)) { + blk_queue_flag_clear(QUEUE_FLAG_INIT_DONE, q); + __blk_mq_unfreeze_queue(q, true); + } else { + if (queue_is_mq(q)) + blk_mq_exit_queue(q); + } } EXPORT_SYMBOL(del_gendisk); +/** + * invalidate_disk - invalidate the disk + * @disk: the struct gendisk to invalidate + * + * A helper to invalidates the disk. It will clean the disk's associated + * buffer/page caches and reset its internal states so that the disk + * can be reused by the drivers. + * + * Context: can sleep + */ +void invalidate_disk(struct gendisk *disk) +{ + struct block_device *bdev = disk->part0; + + invalidate_bdev(bdev); + bdev->bd_inode->i_mapping->wb_err = 0; + set_capacity(disk, 0); +} +EXPORT_SYMBOL(invalidate_disk); + /* sysfs access to bad-blocks list. */ static ssize_t disk_badblocks_show(struct device *dev, struct device_attribute *attr, @@ -860,136 +775,27 @@ static ssize_t disk_badblocks_store(struct device *dev, return badblocks_store(disk->bb, page, len, 0); } -/** - * get_gendisk - get partitioning information for a given device - * @devt: device to get partitioning information for - * @partno: returned partition index - * - * This function gets the structure containing partitioning - * information for the given device @devt. - */ -struct gendisk *get_gendisk(dev_t devt, int *partno) +#ifdef CONFIG_BLOCK_LEGACY_AUTOLOAD +void blk_request_module(dev_t devt) { - struct gendisk *disk = NULL; - - if (MAJOR(devt) != BLOCK_EXT_MAJOR) { - struct kobject *kobj; - - kobj = kobj_lookup(bdev_map, devt, partno); - if (kobj) - disk = dev_to_disk(kobj_to_dev(kobj)); - } else { - struct hd_struct *part; + unsigned int major = MAJOR(devt); + struct blk_major_name **n; - spin_lock_bh(&ext_devt_lock); - part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt))); - if (part && get_disk_and_module(part_to_disk(part))) { - *partno = part->partno; - disk = part_to_disk(part); + mutex_lock(&major_names_lock); + for (n = &major_names[major_to_index(major)]; *n; n = &(*n)->next) { + if ((*n)->major == major && (*n)->probe) { + (*n)->probe(devt); + mutex_unlock(&major_names_lock); + return; } - spin_unlock_bh(&ext_devt_lock); } + mutex_unlock(&major_names_lock); - if (!disk) - return NULL; - - /* - * Synchronize with del_gendisk() to not return disk that is being - * destroyed. - */ - down_read(&disk->lookup_sem); - if (unlikely((disk->flags & GENHD_FL_HIDDEN) || - !(disk->flags & GENHD_FL_UP))) { - up_read(&disk->lookup_sem); - put_disk_and_module(disk); - disk = NULL; - } else { - up_read(&disk->lookup_sem); - } - return disk; -} -EXPORT_SYMBOL(get_gendisk); - -/** - * bdget_disk - do bdget() by gendisk and partition number - * @disk: gendisk of interest - * @partno: partition number - * - * Find partition @partno from @disk, do bdget() on it. - * - * CONTEXT: - * Don't care. - * - * RETURNS: - * Resulting block_device on success, NULL on failure. - */ -struct block_device *bdget_disk(struct gendisk *disk, int partno) -{ - struct hd_struct *part; - struct block_device *bdev = NULL; - - part = disk_get_part(disk, partno); - if (part) - bdev = bdget(part_devt(part)); - disk_put_part(part); - - return bdev; -} -EXPORT_SYMBOL(bdget_disk); - -/* - * print a full list of all partitions - intended for places where the root - * filesystem can't be mounted and thus to give the victim some idea of what - * went wrong - */ -void __init printk_all_partitions(void) -{ - struct class_dev_iter iter; - struct device *dev; - - class_dev_iter_init(&iter, &block_class, NULL, &disk_type); - while ((dev = class_dev_iter_next(&iter))) { - struct gendisk *disk = dev_to_disk(dev); - struct disk_part_iter piter; - struct hd_struct *part; - char name_buf[BDEVNAME_SIZE]; - char devt_buf[BDEVT_SIZE]; - - /* - * Don't show empty devices or things that have been - * suppressed - */ - if (get_capacity(disk) == 0 || - (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)) - continue; - - /* - * Note, unlike /proc/partitions, I am showing the - * numbers in hex - the same format as the root= - * option takes. - */ - disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0); - while ((part = disk_part_iter_next(&piter))) { - bool is_part0 = part == &disk->part0; - - printk("%s%s %10llu %s %s", is_part0 ? "" : " ", - bdevt_str(part_devt(part), devt_buf), - (unsigned long long)part_nr_sects_read(part) >> 1 - , disk_name(disk, part->partno, name_buf), - part->info ? part->info->uuid : ""); - if (is_part0) { - if (dev->parent && dev->parent->driver) - printk(" driver: %s\n", - dev->parent->driver->name); - else - printk(" (driver?)\n"); - } else - printk("\n"); - } - disk_part_iter_exit(&piter); - } - class_dev_iter_exit(&iter); + if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0) + /* Make old-style 2.4 aliases work */ + request_module("block-major-%d", MAJOR(devt)); } +#endif /* CONFIG_BLOCK_LEGACY_AUTOLOAD */ #ifdef CONFIG_PROC_FS /* iterator */ @@ -1051,26 +857,21 @@ static void *show_partition_start(struct seq_file *seqf, loff_t *pos) static int show_partition(struct seq_file *seqf, void *v) { struct gendisk *sgp = v; - struct disk_part_iter piter; - struct hd_struct *part; - char buf[BDEVNAME_SIZE]; + struct block_device *part; + unsigned long idx; - /* Don't show non-partitionable removeable devices or empty devices */ - if (!get_capacity(sgp) || (!disk_max_parts(sgp) && - (sgp->flags & GENHD_FL_REMOVABLE))) - return 0; - if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO) + if (!get_capacity(sgp) || (sgp->flags & GENHD_FL_HIDDEN)) return 0; - /* show the full disk and all non-0 size partitions of it */ - disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0); - while ((part = disk_part_iter_next(&piter))) - seq_printf(seqf, "%4d %7d %10llu %s\n", - MAJOR(part_devt(part)), MINOR(part_devt(part)), - (unsigned long long)part_nr_sects_read(part) >> 1, - disk_name(sgp, part->partno, buf)); - disk_part_iter_exit(&piter); - + rcu_read_lock(); + xa_for_each(&sgp->part_tbl, idx, part) { + if (!bdev_nr_sectors(part)) + continue; + seq_printf(seqf, "%4d %7d %10llu %pg\n", + MAJOR(part->bd_dev), MINOR(part->bd_dev), + bdev_nr_sectors(part) >> 1, part); + } + rcu_read_unlock(); return 0; } @@ -1082,31 +883,19 @@ static const struct seq_operations partitions_op = { }; #endif - -static struct kobject *base_probe(dev_t devt, int *partno, void *data) -{ - if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0) - /* Make old-style 2.4 aliases work */ - request_module("block-major-%d", MAJOR(devt)); - return NULL; -} - static int __init genhd_device_init(void) { int error; - block_class.dev_kobj = sysfs_dev_block_kobj; error = class_register(&block_class); if (unlikely(error)) return error; - bdev_map = kobj_map_init(base_probe, &block_class_lock); blk_dev_init(); register_blkdev(BLOCK_EXT_MAJOR, "blkext"); /* create top-level block dir */ - if (!sysfs_deprecated) - block_depr = kobject_create_and_add("block", NULL); + block_depr = kobject_create_and_add("block", NULL); return 0; } @@ -1125,7 +914,8 @@ static ssize_t disk_ext_range_show(struct device *dev, { struct gendisk *disk = dev_to_disk(dev); - return sprintf(buf, "%d\n", disk_max_parts(disk)); + return sprintf(buf, "%d\n", + (disk->flags & GENHD_FL_NO_PART) ? 1 : DISK_MAX_PARTS); } static ssize_t disk_removable_show(struct device *dev, @@ -1154,12 +944,81 @@ static ssize_t disk_ro_show(struct device *dev, return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0); } +ssize_t part_size_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%llu\n", bdev_nr_sectors(dev_to_bdev(dev))); +} + +ssize_t part_stat_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct block_device *bdev = dev_to_bdev(dev); + struct request_queue *q = bdev_get_queue(bdev); + struct disk_stats stat; + unsigned int inflight; + + if (queue_is_mq(q)) + inflight = blk_mq_in_flight(q, bdev); + else + inflight = part_in_flight(bdev); + + if (inflight) { + part_stat_lock(); + update_io_ticks(bdev, jiffies, true); + part_stat_unlock(); + } + part_stat_read_all(bdev, &stat); + return sprintf(buf, + "%8lu %8lu %8llu %8u " + "%8lu %8lu %8llu %8u " + "%8u %8u %8u " + "%8lu %8lu %8llu %8u " + "%8lu %8u" + "\n", + stat.ios[STAT_READ], + stat.merges[STAT_READ], + (unsigned long long)stat.sectors[STAT_READ], + (unsigned int)div_u64(stat.nsecs[STAT_READ], NSEC_PER_MSEC), + stat.ios[STAT_WRITE], + stat.merges[STAT_WRITE], + (unsigned long long)stat.sectors[STAT_WRITE], + (unsigned int)div_u64(stat.nsecs[STAT_WRITE], NSEC_PER_MSEC), + inflight, + jiffies_to_msecs(stat.io_ticks), + (unsigned int)div_u64(stat.nsecs[STAT_READ] + + stat.nsecs[STAT_WRITE] + + stat.nsecs[STAT_DISCARD] + + stat.nsecs[STAT_FLUSH], + NSEC_PER_MSEC), + stat.ios[STAT_DISCARD], + stat.merges[STAT_DISCARD], + (unsigned long long)stat.sectors[STAT_DISCARD], + (unsigned int)div_u64(stat.nsecs[STAT_DISCARD], NSEC_PER_MSEC), + stat.ios[STAT_FLUSH], + (unsigned int)div_u64(stat.nsecs[STAT_FLUSH], NSEC_PER_MSEC)); +} + +ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct block_device *bdev = dev_to_bdev(dev); + struct request_queue *q = bdev_get_queue(bdev); + unsigned int inflight[2]; + + if (queue_is_mq(q)) + blk_mq_in_flight_rw(q, bdev, inflight); + else + part_in_flight_rw(bdev, inflight); + + return sprintf(buf, "%8u %8u\n", inflight[0], inflight[1]); +} + static ssize_t disk_capability_show(struct device *dev, struct device_attribute *attr, char *buf) { - struct gendisk *disk = dev_to_disk(dev); - - return sprintf(buf, "%x\n", disk->flags); + dev_warn_once(dev, "the capability attribute has been deprecated.\n"); + return sprintf(buf, "0\n"); } static ssize_t disk_alignment_offset_show(struct device *dev, @@ -1168,7 +1027,7 @@ static ssize_t disk_alignment_offset_show(struct device *dev, { struct gendisk *disk = dev_to_disk(dev); - return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue)); + return sprintf(buf, "%d\n", bdev_alignment_offset(disk->part0)); } static ssize_t disk_discard_alignment_show(struct device *dev, @@ -1177,7 +1036,15 @@ static ssize_t disk_discard_alignment_show(struct device *dev, { struct gendisk *disk = dev_to_disk(dev); - return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue)); + return sprintf(buf, "%d\n", bdev_alignment_offset(disk->part0)); +} + +static ssize_t diskseq_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct gendisk *disk = dev_to_disk(dev); + + return sprintf(buf, "%llu\n", disk->diskseq); } static DEVICE_ATTR(range, 0444, disk_range_show, NULL); @@ -1192,10 +1059,31 @@ static DEVICE_ATTR(capability, 0444, disk_capability_show, NULL); static DEVICE_ATTR(stat, 0444, part_stat_show, NULL); static DEVICE_ATTR(inflight, 0444, part_inflight_show, NULL); static DEVICE_ATTR(badblocks, 0644, disk_badblocks_show, disk_badblocks_store); +static DEVICE_ATTR(diskseq, 0444, diskseq_show, NULL); + #ifdef CONFIG_FAIL_MAKE_REQUEST +ssize_t part_fail_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", dev_to_bdev(dev)->bd_make_it_fail); +} + +ssize_t part_fail_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int i; + + if (count > 0 && sscanf(buf, "%d", &i) > 0) + dev_to_bdev(dev)->bd_make_it_fail = i; + + return count; +} + static struct device_attribute dev_attr_fail = __ATTR(make-it-fail, 0644, part_fail_show, part_fail_store); -#endif +#endif /* CONFIG_FAIL_MAKE_REQUEST */ + #ifdef CONFIG_FAIL_IO_TIMEOUT static struct device_attribute dev_attr_fail_timeout = __ATTR(io-timeout-fail, 0644, part_timeout_show, part_timeout_store); @@ -1214,6 +1102,10 @@ static struct attribute *disk_attrs[] = { &dev_attr_stat.attr, &dev_attr_inflight.attr, &dev_attr_badblocks.attr, + &dev_attr_events.attr, + &dev_attr_events_async.attr, + &dev_attr_events_poll_msecs.attr, + &dev_attr_diskseq.attr, #ifdef CONFIG_FAIL_MAKE_REQUEST &dev_attr_fail.attr, #endif @@ -1240,114 +1132,91 @@ static struct attribute_group disk_attr_group = { static const struct attribute_group *disk_attr_groups[] = { &disk_attr_group, +#ifdef CONFIG_BLK_DEV_IO_TRACE + &blk_trace_attr_group, +#endif +#ifdef CONFIG_BLK_DEV_INTEGRITY + &blk_integrity_attr_group, +#endif NULL }; /** - * 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 + * disk_release - releases all allocated resources of the gendisk + * @dev: the device representing this disk + * + * This function releases all allocated resources of the gendisk. * - * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The - * original ptbl is freed using RCU callback. + * Drivers which used __device_add_disk() have a gendisk with a request_queue + * assigned. Since the request_queue sits on top of the gendisk for these + * drivers we also call blk_put_queue() for them, and we expect the + * request_queue refcount to reach 0 at this point, and so the request_queue + * will also be freed prior to the disk. * - * LOCKING: - * Matching bd_mutex locked or the caller is the only user of @disk. + * Context: can sleep */ -static void disk_replace_part_tbl(struct gendisk *disk, - struct disk_part_tbl *new_ptbl) +static void disk_release(struct device *dev) { - struct disk_part_tbl *old_ptbl = - rcu_dereference_protected(disk->part_tbl, 1); + struct gendisk *disk = dev_to_disk(dev); - rcu_assign_pointer(disk->part_tbl, new_ptbl); + might_sleep(); + WARN_ON_ONCE(disk_live(disk)); - 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; + blk_trace_remove(disk->queue); /* - * check for int overflow, since we can get here from blkpg_ioctl() - * with a user passed 'partno'. + * To undo the all initialization from blk_mq_init_allocated_queue in + * case of a probe failure where add_disk is never called we have to + * call blk_mq_exit_queue here. We can't do this for the more common + * teardown case (yet) as the tagset can be gone by the time the disk + * is released once it was added. */ - target = partno + 1; - if (target < 0) - return -EINVAL; + if (queue_is_mq(disk->queue) && + test_bit(GD_OWNS_QUEUE, &disk->state) && + !test_bit(GD_ADDED, &disk->state)) + blk_mq_exit_queue(disk->queue); - /* disk_max_parts() is zero during initialization, ignore if so */ - if (disk_max_parts(disk) && target > disk_max_parts(disk)) - return -EINVAL; + blkcg_exit_disk(disk); - if (target <= len) - return 0; + bioset_exit(&disk->bio_split); - new_ptbl = kzalloc_node(struct_size(new_ptbl, part, target), GFP_KERNEL, - disk->node_id); - if (!new_ptbl) - return -ENOMEM; + disk_release_events(disk); + kfree(disk->random); + disk_free_zone_bitmaps(disk); + xa_destroy(&disk->part_tbl); - new_ptbl->len = target; + disk->queue->disk = NULL; + blk_put_queue(disk->queue); - for (i = 0; i < len; i++) - rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]); + if (test_bit(GD_ADDED, &disk->state) && disk->fops->free_disk) + disk->fops->free_disk(disk); - disk_replace_part_tbl(disk, new_ptbl); - return 0; + iput(disk->part0->bd_inode); /* frees the disk */ } -static void disk_release(struct device *dev) +static int block_uevent(const struct device *dev, struct kobj_uevent_env *env) { - struct gendisk *disk = dev_to_disk(dev); + const struct gendisk *disk = dev_to_disk(dev); - blk_free_devt(dev->devt); - disk_release_events(disk); - kfree(disk->random); - disk_replace_part_tbl(disk, NULL); - hd_free_part(&disk->part0); - if (disk->queue) - blk_put_queue(disk->queue); - kfree(disk); + return add_uevent_var(env, "DISKSEQ=%llu", disk->diskseq); } + struct class block_class = { .name = "block", + .dev_uevent = block_uevent, }; -static char *block_devnode(struct device *dev, umode_t *mode, +static char *block_devnode(const struct device *dev, umode_t *mode, kuid_t *uid, kgid_t *gid) { struct gendisk *disk = dev_to_disk(dev); - if (disk->devnode) - return disk->devnode(disk, mode); + if (disk->fops->devnode) + return disk->fops->devnode(disk, mode); return NULL; } -static const struct device_type disk_type = { +const struct device_type disk_type = { .name = "disk", .groups = disk_attr_groups, .release = disk_release, @@ -1365,10 +1234,10 @@ static const struct device_type disk_type = { static int diskstats_show(struct seq_file *seqf, void *v) { struct gendisk *gp = v; - struct disk_part_iter piter; - struct hd_struct *hd; - char buf[BDEVNAME_SIZE]; + struct block_device *hd; unsigned int inflight; + struct disk_stats stat; + unsigned long idx; /* if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next) @@ -1378,34 +1247,57 @@ static int diskstats_show(struct seq_file *seqf, void *v) "\n\n"); */ - disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0); - while ((hd = disk_part_iter_next(&piter))) { - inflight = part_in_flight(gp->queue, hd); - seq_printf(seqf, "%4d %7d %s " + rcu_read_lock(); + xa_for_each(&gp->part_tbl, idx, hd) { + if (bdev_is_partition(hd) && !bdev_nr_sectors(hd)) + continue; + if (queue_is_mq(gp->queue)) + inflight = blk_mq_in_flight(gp->queue, hd); + else + inflight = part_in_flight(hd); + + if (inflight) { + part_stat_lock(); + update_io_ticks(hd, jiffies, true); + part_stat_unlock(); + } + part_stat_read_all(hd, &stat); + seq_printf(seqf, "%4d %7d %pg " "%lu %lu %lu %u " "%lu %lu %lu %u " "%u %u %u " - "%lu %lu %lu %u\n", - MAJOR(part_devt(hd)), MINOR(part_devt(hd)), - disk_name(gp, hd->partno, buf), - part_stat_read(hd, ios[STAT_READ]), - part_stat_read(hd, merges[STAT_READ]), - part_stat_read(hd, sectors[STAT_READ]), - (unsigned int)part_stat_read_msecs(hd, STAT_READ), - part_stat_read(hd, ios[STAT_WRITE]), - part_stat_read(hd, merges[STAT_WRITE]), - part_stat_read(hd, sectors[STAT_WRITE]), - (unsigned int)part_stat_read_msecs(hd, STAT_WRITE), + "%lu %lu %lu %u " + "%lu %u" + "\n", + MAJOR(hd->bd_dev), MINOR(hd->bd_dev), hd, + stat.ios[STAT_READ], + stat.merges[STAT_READ], + stat.sectors[STAT_READ], + (unsigned int)div_u64(stat.nsecs[STAT_READ], + NSEC_PER_MSEC), + stat.ios[STAT_WRITE], + stat.merges[STAT_WRITE], + stat.sectors[STAT_WRITE], + (unsigned int)div_u64(stat.nsecs[STAT_WRITE], + NSEC_PER_MSEC), inflight, - jiffies_to_msecs(part_stat_read(hd, io_ticks)), - jiffies_to_msecs(part_stat_read(hd, time_in_queue)), - part_stat_read(hd, ios[STAT_DISCARD]), - part_stat_read(hd, merges[STAT_DISCARD]), - part_stat_read(hd, sectors[STAT_DISCARD]), - (unsigned int)part_stat_read_msecs(hd, STAT_DISCARD) + jiffies_to_msecs(stat.io_ticks), + (unsigned int)div_u64(stat.nsecs[STAT_READ] + + stat.nsecs[STAT_WRITE] + + stat.nsecs[STAT_DISCARD] + + stat.nsecs[STAT_FLUSH], + NSEC_PER_MSEC), + stat.ios[STAT_DISCARD], + stat.merges[STAT_DISCARD], + stat.sectors[STAT_DISCARD], + (unsigned int)div_u64(stat.nsecs[STAT_DISCARD], + NSEC_PER_MSEC), + stat.ios[STAT_FLUSH], + (unsigned int)div_u64(stat.nsecs[STAT_FLUSH], + NSEC_PER_MSEC) ); } - disk_part_iter_exit(&piter); + rcu_read_unlock(); return 0; } @@ -1426,137 +1318,118 @@ static int __init proc_genhd_init(void) module_init(proc_genhd_init); #endif /* CONFIG_PROC_FS */ -dev_t blk_lookup_devt(const char *name, int partno) +dev_t part_devt(struct gendisk *disk, u8 partno) { - dev_t devt = MKDEV(0, 0); - struct class_dev_iter iter; - struct device *dev; - - class_dev_iter_init(&iter, &block_class, NULL, &disk_type); - while ((dev = class_dev_iter_next(&iter))) { - struct gendisk *disk = dev_to_disk(dev); - struct hd_struct *part; + struct block_device *part; + dev_t devt = 0; - if (strcmp(dev_name(dev), name)) - continue; + rcu_read_lock(); + part = xa_load(&disk->part_tbl, partno); + if (part) + devt = part->bd_dev; + rcu_read_unlock(); - if (partno < disk->minors) { - /* We need to return the right devno, even - * if the partition doesn't exist yet. - */ - devt = MKDEV(MAJOR(dev->devt), - MINOR(dev->devt) + partno); - break; - } - part = disk_get_part(disk, partno); - if (part) { - devt = part_devt(part); - disk_put_part(part); - break; - } - disk_put_part(part); - } - class_dev_iter_exit(&iter); return devt; } -EXPORT_SYMBOL(blk_lookup_devt); -struct gendisk *__alloc_disk_node(int minors, int node_id) +struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id, + struct lock_class_key *lkclass) { struct gendisk *disk; - struct disk_part_tbl *ptbl; - - if (minors > DISK_MAX_PARTS) { - printk(KERN_ERR - "block: can't allocate more than %d partitions\n", - DISK_MAX_PARTS); - minors = DISK_MAX_PARTS; - } disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id); - if (disk) { - if (!init_part_stats(&disk->part0)) { - kfree(disk); - return NULL; - } - init_rwsem(&disk->lookup_sem); - disk->node_id = node_id; - if (disk_expand_part_tbl(disk, 0)) { - free_part_stats(&disk->part0); - kfree(disk); - return NULL; - } - ptbl = rcu_dereference_protected(disk->part_tbl, 1); - rcu_assign_pointer(ptbl->part[0], &disk->part0); - - /* - * set_capacity() and get_capacity() currently don't use - * seqcounter to read/update the part0->nr_sects. Still init - * the counter as we can read the sectors in IO submission - * patch using seqence counters. - * - * TODO: Ideally set_capacity() and get_capacity() should be - * converted to make use of bd_mutex and sequence counters. - */ - seqcount_init(&disk->part0.nr_sects_seq); - if (hd_ref_init(&disk->part0)) { - hd_free_part(&disk->part0); - kfree(disk); - return NULL; - } + if (!disk) + return NULL; - disk->minors = minors; - rand_initialize_disk(disk); - disk_to_dev(disk)->class = &block_class; - disk_to_dev(disk)->type = &disk_type; - device_initialize(disk_to_dev(disk)); - } + if (bioset_init(&disk->bio_split, BIO_POOL_SIZE, 0, 0)) + goto out_free_disk; + + disk->bdi = bdi_alloc(node_id); + if (!disk->bdi) + goto out_free_bioset; + + /* bdev_alloc() might need the queue, set before the first call */ + disk->queue = q; + + disk->part0 = bdev_alloc(disk, 0); + if (!disk->part0) + goto out_free_bdi; + + disk->node_id = node_id; + mutex_init(&disk->open_mutex); + xa_init(&disk->part_tbl); + if (xa_insert(&disk->part_tbl, 0, disk->part0, GFP_KERNEL)) + goto out_destroy_part_tbl; + + if (blkcg_init_disk(disk)) + goto out_erase_part0; + + rand_initialize_disk(disk); + disk_to_dev(disk)->class = &block_class; + disk_to_dev(disk)->type = &disk_type; + device_initialize(disk_to_dev(disk)); + inc_diskseq(disk); + q->disk = disk; + lockdep_init_map(&disk->lockdep_map, "(bio completion)", lkclass, 0); +#ifdef CONFIG_BLOCK_HOLDER_DEPRECATED + INIT_LIST_HEAD(&disk->slave_bdevs); +#endif return disk; + +out_erase_part0: + xa_erase(&disk->part_tbl, 0); +out_destroy_part_tbl: + xa_destroy(&disk->part_tbl); + disk->part0->bd_disk = NULL; + iput(disk->part0->bd_inode); +out_free_bdi: + bdi_put(disk->bdi); +out_free_bioset: + bioset_exit(&disk->bio_split); +out_free_disk: + kfree(disk); + return NULL; } -EXPORT_SYMBOL(__alloc_disk_node); -struct kobject *get_disk_and_module(struct gendisk *disk) +struct gendisk *__blk_alloc_disk(int node, struct lock_class_key *lkclass) { - struct module *owner; - struct kobject *kobj; + struct request_queue *q; + struct gendisk *disk; - if (!disk->fops) - return NULL; - owner = disk->fops->owner; - if (owner && !try_module_get(owner)) + q = blk_alloc_queue(node); + if (!q) return NULL; - kobj = kobject_get_unless_zero(&disk_to_dev(disk)->kobj); - if (kobj == NULL) { - module_put(owner); + + disk = __alloc_disk_node(q, node, lkclass); + if (!disk) { + blk_put_queue(q); return NULL; } - return kobj; - + set_bit(GD_OWNS_QUEUE, &disk->state); + return disk; } -EXPORT_SYMBOL(get_disk_and_module); +EXPORT_SYMBOL(__blk_alloc_disk); +/** + * put_disk - decrements the gendisk refcount + * @disk: the struct gendisk to decrement the refcount for + * + * This decrements the refcount for the struct gendisk. When this reaches 0 + * we'll have disk_release() called. + * + * Note: for blk-mq disk put_disk must be called before freeing the tag_set + * when handling probe errors (that is before add_disk() is called). + * + * Context: Any context, but the last reference must not be dropped from + * atomic context. + */ void put_disk(struct gendisk *disk) { if (disk) - kobject_put(&disk_to_dev(disk)->kobj); + put_device(disk_to_dev(disk)); } EXPORT_SYMBOL(put_disk); -/* - * This is a counterpart of get_disk_and_module() and thus also of - * get_gendisk(). - */ -void put_disk_and_module(struct gendisk *disk) -{ - if (disk) { - struct module *owner = disk->fops->owner; - - put_disk(disk); - module_put(owner); - } -} -EXPORT_SYMBOL(put_disk_and_module); - static void set_disk_ro_uevent(struct gendisk *gd, int ro) { char event[] = "DISK_RO=1"; @@ -1567,514 +1440,29 @@ static void set_disk_ro_uevent(struct gendisk *gd, int ro) kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp); } -void set_device_ro(struct block_device *bdev, int flag) -{ - bdev->bd_part->policy = flag; -} - -EXPORT_SYMBOL(set_device_ro); - -void set_disk_ro(struct gendisk *disk, int flag) -{ - struct disk_part_iter piter; - struct hd_struct *part; - - if (disk->part0.policy != flag) { - set_disk_ro_uevent(disk, flag); - disk->part0.policy = flag; - } - - disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); - while ((part = disk_part_iter_next(&piter))) - part->policy = flag; - disk_part_iter_exit(&piter); -} - -EXPORT_SYMBOL(set_disk_ro); - -int bdev_read_only(struct block_device *bdev) -{ - if (!bdev) - return 0; - return bdev->bd_part->policy; -} - -EXPORT_SYMBOL(bdev_read_only); - -int invalidate_partition(struct gendisk *disk, int partno) -{ - int res = 0; - struct block_device *bdev = bdget_disk(disk, partno); - if (bdev) { - fsync_bdev(bdev); - res = __invalidate_device(bdev, true); - bdput(bdev); - } - return res; -} - -EXPORT_SYMBOL(invalidate_partition); - -/* - * Disk events - monitor disk events like media change and eject request. - */ -struct disk_events { - struct list_head node; /* all disk_event's */ - struct gendisk *disk; /* the associated disk */ - spinlock_t lock; - - struct mutex block_mutex; /* protects blocking */ - int block; /* event blocking depth */ - unsigned int pending; /* events already sent out */ - unsigned int clearing; /* events being cleared */ - - long poll_msecs; /* interval, -1 for default */ - struct delayed_work dwork; -}; - -static const char *disk_events_strs[] = { - [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "media_change", - [ilog2(DISK_EVENT_EJECT_REQUEST)] = "eject_request", -}; - -static char *disk_uevents[] = { - [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "DISK_MEDIA_CHANGE=1", - [ilog2(DISK_EVENT_EJECT_REQUEST)] = "DISK_EJECT_REQUEST=1", -}; - -/* list of all disk_events */ -static DEFINE_MUTEX(disk_events_mutex); -static LIST_HEAD(disk_events); - -/* disable in-kernel polling by default */ -static unsigned long disk_events_dfl_poll_msecs; - -static unsigned long disk_events_poll_jiffies(struct gendisk *disk) -{ - struct disk_events *ev = disk->ev; - long intv_msecs = 0; - - /* - * If device-specific poll interval is set, always use it. If - * the default is being used, poll if the POLL flag is set. - */ - if (ev->poll_msecs >= 0) - intv_msecs = ev->poll_msecs; - else if (disk->event_flags & DISK_EVENT_FLAG_POLL) - intv_msecs = disk_events_dfl_poll_msecs; - - return msecs_to_jiffies(intv_msecs); -} - -/** - * disk_block_events - block and flush disk event checking - * @disk: disk to block events for - * - * On return from this function, it is guaranteed that event checking - * isn't in progress and won't happen until unblocked by - * disk_unblock_events(). Events blocking is counted and the actual - * unblocking happens after the matching number of unblocks are done. - * - * Note that this intentionally does not block event checking from - * disk_clear_events(). - * - * CONTEXT: - * Might sleep. - */ -void disk_block_events(struct gendisk *disk) -{ - struct disk_events *ev = disk->ev; - unsigned long flags; - bool cancel; - - if (!ev) - return; - - /* - * Outer mutex ensures that the first blocker completes canceling - * the event work before further blockers are allowed to finish. - */ - mutex_lock(&ev->block_mutex); - - spin_lock_irqsave(&ev->lock, flags); - cancel = !ev->block++; - spin_unlock_irqrestore(&ev->lock, flags); - - if (cancel) - cancel_delayed_work_sync(&disk->ev->dwork); - - mutex_unlock(&ev->block_mutex); -} - -static void __disk_unblock_events(struct gendisk *disk, bool check_now) -{ - struct disk_events *ev = disk->ev; - unsigned long intv; - unsigned long flags; - - spin_lock_irqsave(&ev->lock, flags); - - if (WARN_ON_ONCE(ev->block <= 0)) - goto out_unlock; - - if (--ev->block) - goto out_unlock; - - intv = disk_events_poll_jiffies(disk); - if (check_now) - queue_delayed_work(system_freezable_power_efficient_wq, - &ev->dwork, 0); - else if (intv) - queue_delayed_work(system_freezable_power_efficient_wq, - &ev->dwork, intv); -out_unlock: - spin_unlock_irqrestore(&ev->lock, flags); -} - -/** - * disk_unblock_events - unblock disk event checking - * @disk: disk to unblock events for - * - * Undo disk_block_events(). When the block count reaches zero, it - * starts events polling if configured. - * - * CONTEXT: - * Don't care. Safe to call from irq context. - */ -void disk_unblock_events(struct gendisk *disk) -{ - if (disk->ev) - __disk_unblock_events(disk, false); -} - -/** - * disk_flush_events - schedule immediate event checking and flushing - * @disk: disk to check and flush events for - * @mask: events to flush - * - * Schedule immediate event checking on @disk if not blocked. Events in - * @mask are scheduled to be cleared from the driver. Note that this - * doesn't clear the events from @disk->ev. - * - * CONTEXT: - * If @mask is non-zero must be called with bdev->bd_mutex held. - */ -void disk_flush_events(struct gendisk *disk, unsigned int mask) -{ - struct disk_events *ev = disk->ev; - - if (!ev) - return; - - spin_lock_irq(&ev->lock); - ev->clearing |= mask; - if (!ev->block) - mod_delayed_work(system_freezable_power_efficient_wq, - &ev->dwork, 0); - spin_unlock_irq(&ev->lock); -} - /** - * disk_clear_events - synchronously check, clear and return pending events - * @disk: disk to fetch and clear events from - * @mask: mask of events to be fetched and cleared - * - * Disk events are synchronously checked and pending events in @mask - * are cleared and returned. This ignores the block count. - * - * CONTEXT: - * Might sleep. - */ -unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask) -{ - const struct block_device_operations *bdops = disk->fops; - struct disk_events *ev = disk->ev; - unsigned int pending; - unsigned int clearing = mask; - - if (!ev) { - /* for drivers still using the old ->media_changed method */ - if ((mask & DISK_EVENT_MEDIA_CHANGE) && - bdops->media_changed && bdops->media_changed(disk)) - return DISK_EVENT_MEDIA_CHANGE; - return 0; - } - - disk_block_events(disk); - - /* - * store the union of mask and ev->clearing on the stack so that the - * race with disk_flush_events does not cause ambiguity (ev->clearing - * can still be modified even if events are blocked). - */ - spin_lock_irq(&ev->lock); - clearing |= ev->clearing; - ev->clearing = 0; - spin_unlock_irq(&ev->lock); - - disk_check_events(ev, &clearing); - /* - * if ev->clearing is not 0, the disk_flush_events got called in the - * middle of this function, so we want to run the workfn without delay. - */ - __disk_unblock_events(disk, ev->clearing ? true : false); - - /* then, fetch and clear pending events */ - spin_lock_irq(&ev->lock); - pending = ev->pending & mask; - ev->pending &= ~mask; - spin_unlock_irq(&ev->lock); - WARN_ON_ONCE(clearing & mask); - - return pending; -} - -/* - * Separate this part out so that a different pointer for clearing_ptr can be - * passed in for disk_clear_events. - */ -static void disk_events_workfn(struct work_struct *work) -{ - struct delayed_work *dwork = to_delayed_work(work); - struct disk_events *ev = container_of(dwork, struct disk_events, dwork); - - disk_check_events(ev, &ev->clearing); -} - -static void disk_check_events(struct disk_events *ev, - unsigned int *clearing_ptr) -{ - struct gendisk *disk = ev->disk; - char *envp[ARRAY_SIZE(disk_uevents) + 1] = { }; - unsigned int clearing = *clearing_ptr; - unsigned int events; - unsigned long intv; - int nr_events = 0, i; - - /* check events */ - events = disk->fops->check_events(disk, clearing); - - /* accumulate pending events and schedule next poll if necessary */ - spin_lock_irq(&ev->lock); - - events &= ~ev->pending; - ev->pending |= events; - *clearing_ptr &= ~clearing; - - intv = disk_events_poll_jiffies(disk); - if (!ev->block && intv) - queue_delayed_work(system_freezable_power_efficient_wq, - &ev->dwork, intv); - - spin_unlock_irq(&ev->lock); - - /* - * Tell userland about new events. Only the events listed in - * @disk->events are reported, and only if DISK_EVENT_FLAG_UEVENT - * is set. Otherwise, events are processed internally but never - * get reported to userland. - */ - for (i = 0; i < ARRAY_SIZE(disk_uevents); i++) - if ((events & disk->events & (1 << i)) && - (disk->event_flags & DISK_EVENT_FLAG_UEVENT)) - envp[nr_events++] = disk_uevents[i]; - - if (nr_events) - kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp); -} - -/* - * A disk events enabled device has the following sysfs nodes under - * its /sys/block/X/ directory. + * 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 * - * events : list of all supported events - * events_async : list of events which can be detected w/o polling - * (always empty, only for backwards compatibility) - * events_poll_msecs : polling interval, 0: disable, -1: system default + * 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. */ -static ssize_t __disk_events_show(unsigned int events, char *buf) +void set_disk_ro(struct gendisk *disk, bool read_only) { - const char *delim = ""; - ssize_t pos = 0; - int i; - - for (i = 0; i < ARRAY_SIZE(disk_events_strs); i++) - if (events & (1 << i)) { - pos += sprintf(buf + pos, "%s%s", - delim, disk_events_strs[i]); - delim = " "; - } - if (pos) - pos += sprintf(buf + pos, "\n"); - return pos; -} - -static ssize_t disk_events_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct gendisk *disk = dev_to_disk(dev); - - if (!(disk->event_flags & DISK_EVENT_FLAG_UEVENT)) - return 0; - - return __disk_events_show(disk->events, buf); -} - -static ssize_t disk_events_async_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - return 0; -} - -static ssize_t disk_events_poll_msecs_show(struct device *dev, - struct device_attribute *attr, - char *buf) -{ - struct gendisk *disk = dev_to_disk(dev); - - if (!disk->ev) - return sprintf(buf, "-1\n"); - - return sprintf(buf, "%ld\n", disk->ev->poll_msecs); -} - -static ssize_t disk_events_poll_msecs_store(struct device *dev, - struct device_attribute *attr, - const char *buf, size_t count) -{ - struct gendisk *disk = dev_to_disk(dev); - long intv; - - if (!count || !sscanf(buf, "%ld", &intv)) - return -EINVAL; - - if (intv < 0 && intv != -1) - return -EINVAL; - - if (!disk->ev) - return -ENODEV; - - disk_block_events(disk); - disk->ev->poll_msecs = intv; - __disk_unblock_events(disk, true); - - return count; -} - -static const DEVICE_ATTR(events, 0444, disk_events_show, NULL); -static const DEVICE_ATTR(events_async, 0444, disk_events_async_show, NULL); -static const DEVICE_ATTR(events_poll_msecs, 0644, - disk_events_poll_msecs_show, - disk_events_poll_msecs_store); - -static const struct attribute *disk_events_attrs[] = { - &dev_attr_events.attr, - &dev_attr_events_async.attr, - &dev_attr_events_poll_msecs.attr, - NULL, -}; - -/* - * The default polling interval can be specified by the kernel - * parameter block.events_dfl_poll_msecs which defaults to 0 - * (disable). This can also be modified runtime by writing to - * /sys/module/block/parameters/events_dfl_poll_msecs. - */ -static int disk_events_set_dfl_poll_msecs(const char *val, - const struct kernel_param *kp) -{ - struct disk_events *ev; - int ret; - - ret = param_set_ulong(val, kp); - if (ret < 0) - return ret; - - mutex_lock(&disk_events_mutex); - - list_for_each_entry(ev, &disk_events, node) - disk_flush_events(ev->disk, 0); - - mutex_unlock(&disk_events_mutex); - - return 0; -} - -static const struct kernel_param_ops disk_events_dfl_poll_msecs_param_ops = { - .set = disk_events_set_dfl_poll_msecs, - .get = param_get_ulong, -}; - -#undef MODULE_PARAM_PREFIX -#define MODULE_PARAM_PREFIX "block." - -module_param_cb(events_dfl_poll_msecs, &disk_events_dfl_poll_msecs_param_ops, - &disk_events_dfl_poll_msecs, 0644); - -/* - * disk_{alloc|add|del|release}_events - initialize and destroy disk_events. - */ -static void disk_alloc_events(struct gendisk *disk) -{ - struct disk_events *ev; - - if (!disk->fops->check_events || !disk->events) - return; - - ev = kzalloc(sizeof(*ev), GFP_KERNEL); - if (!ev) { - pr_warn("%s: failed to initialize events\n", disk->disk_name); - return; - } - - INIT_LIST_HEAD(&ev->node); - ev->disk = disk; - spin_lock_init(&ev->lock); - mutex_init(&ev->block_mutex); - ev->block = 1; - ev->poll_msecs = -1; - INIT_DELAYED_WORK(&ev->dwork, disk_events_workfn); - - disk->ev = ev; -} - -static void disk_add_events(struct gendisk *disk) -{ - /* FIXME: error handling */ - if (sysfs_create_files(&disk_to_dev(disk)->kobj, disk_events_attrs) < 0) - pr_warn("%s: failed to create sysfs files for events\n", - disk->disk_name); - - if (!disk->ev) - return; - - mutex_lock(&disk_events_mutex); - list_add_tail(&disk->ev->node, &disk_events); - mutex_unlock(&disk_events_mutex); - - /* - * Block count is initialized to 1 and the following initial - * unblock kicks it into action. - */ - __disk_unblock_events(disk, true); -} - -static void disk_del_events(struct gendisk *disk) -{ - if (disk->ev) { - disk_block_events(disk); - - mutex_lock(&disk_events_mutex); - list_del_init(&disk->ev->node); - mutex_unlock(&disk_events_mutex); + 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; } - - sysfs_remove_files(&disk_to_dev(disk)->kobj, disk_events_attrs); + set_disk_ro_uevent(disk, read_only); } +EXPORT_SYMBOL(set_disk_ro); -static void disk_release_events(struct gendisk *disk) +void inc_diskseq(struct gendisk *disk) { - /* the block count should be 1 from disk_del_events() */ - WARN_ON_ONCE(disk->ev && disk->ev->block != 1); - kfree(disk->ev); + disk->diskseq = atomic64_inc_return(&diskseq); } |