| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Tejun Heo | 3878 | 46.01% | 34 | 14.41% |
| Andrew Morton | 645 | 7.65% | 16 | 6.78% |
| Al Viro | 548 | 6.50% | 26 | 11.02% |
| Kay Sievers | 382 | 4.53% | 11 | 4.66% |
| Jens Axboe | 326 | 3.87% | 9 | 3.81% |
| Christoph Hellwig | 274 | 3.25% | 7 | 2.97% |
| Jan Kara | 177 | 2.10% | 10 | 4.24% |
| Hannes Reinecke | 165 | 1.96% | 3 | 1.27% |
| Vishal Verma | 136 | 1.61% | 1 | 0.42% |
| Martin K. Petersen | 132 | 1.57% | 4 | 1.69% |
| Mikulas Patocka | 124 | 1.47% | 2 | 0.85% |
| Greg Kroah-Hartman | 115 | 1.36% | 10 | 4.24% |
| Dan J Williams | 111 | 1.32% | 6 | 2.54% |
| Linus Torvalds | 98 | 1.16% | 5 | 2.12% |
| Derek Basehore | 82 | 0.97% | 1 | 0.42% |
| Patrick Mochel | 78 | 0.93% | 5 | 2.12% |
| Omar Sandoval | 78 | 0.93% | 2 | 0.85% |
| Dave Jones | 76 | 0.90% | 1 | 0.42% |
| Mike Snitzer | 73 | 0.87% | 2 | 0.85% |
| Jerome Marchand | 72 | 0.85% | 3 | 1.27% |
| Stanislaw Gruszka | 71 | 0.84% | 1 | 0.42% |
| David Alan Gilbert | 71 | 0.84% | 1 | 0.42% |
| Michael Callahan | 49 | 0.58% | 2 | 0.85% |
| Arnaldo Carvalho de Melo | 44 | 0.52% | 1 | 0.42% |
| Alexey Dobriyan | 42 | 0.50% | 2 | 0.85% |
| Logan Gunthorpe | 41 | 0.49% | 1 | 0.42% |
| Joe Korty | 37 | 0.44% | 1 | 0.42% |
| Neil Brown | 35 | 0.42% | 2 | 0.85% |
| Kristen Carlson Accardi | 32 | 0.38% | 2 | 0.85% |
| Bart Van Assche | 32 | 0.38% | 2 | 0.85% |
| Peter Zijlstra | 29 | 0.34% | 1 | 0.42% |
| Akinobu Mita | 26 | 0.31% | 3 | 1.27% |
| Keith Busch | 25 | 0.30% | 1 | 0.42% |
| Linus Torvalds (pre-git) | 24 | 0.28% | 8 | 3.39% |
| Olaf Hering | 23 | 0.27% | 1 | 0.42% |
| Vivek Goyal | 23 | 0.27% | 1 | 0.42% |
| Lei Ming | 21 | 0.25% | 2 | 0.85% |
| Ming Lei | 21 | 0.25% | 1 | 0.42% |
| Neil Horman | 19 | 0.23% | 1 | 0.42% |
| Joe Perches | 18 | 0.21% | 2 | 0.85% |
| Nikanth Karthikesan | 16 | 0.19% | 1 | 0.42% |
| Roland McGrath | 12 | 0.14% | 1 | 0.42% |
| Stephen Warren | 11 | 0.13% | 1 | 0.42% |
| Christoph Lameter | 10 | 0.12% | 1 | 0.42% |
| weiping zhang | 10 | 0.12% | 1 | 0.42% |
| Rusty Russell | 10 | 0.12% | 2 | 0.85% |
| Adrian Bunk | 9 | 0.11% | 3 | 1.27% |
| Will Drewry | 8 | 0.09% | 2 | 0.85% |
| Tomas Henzl | 8 | 0.09% | 1 | 0.42% |
| Art Haas | 8 | 0.09% | 1 | 0.42% |
| Jes Sorensen | 7 | 0.08% | 1 | 0.42% |
| Yanmin Zhang | 7 | 0.08% | 1 | 0.42% |
| Cheng Renquan | 6 | 0.07% | 1 | 0.42% |
| Vegard Nossum | 6 | 0.07% | 1 | 0.42% |
| Randy Dunlap | 6 | 0.07% | 4 | 1.69% |
| Andi Kleen | 5 | 0.06% | 1 | 0.42% |
| Srivatsa S. Bhat | 5 | 0.06% | 1 | 0.42% |
| Divyesh Shah | 5 | 0.06% | 1 | 0.42% |
| Viresh Kumar | 4 | 0.05% | 1 | 0.42% |
| Anton Blanchard | 3 | 0.04% | 1 | 0.42% |
| Harvey Harrison | 2 | 0.02% | 1 | 0.42% |
| Lai Jiangshan | 2 | 0.02% | 1 | 0.42% |
| Yang Zhang | 2 | 0.02% | 2 | 0.85% |
| Byungchul Park | 2 | 0.02% | 1 | 0.42% |
| Jan Engelhardt | 2 | 0.02% | 1 | 0.42% |
| Kees Cook | 2 | 0.02% | 1 | 0.42% |
| Masanari Iida | 1 | 0.01% | 1 | 0.42% |
| Li Zefan | 1 | 0.01% | 1 | 0.42% |
| Benjamin Collins | 1 | 0.01% | 1 | 0.42% |
| Andries E. Brouwer | 1 | 0.01% | 1 | 0.42% |
| Mika Kukkonen | 1 | 0.01% | 1 | 0.42% |
| Colin Ian King | 1 | 0.01% | 1 | 0.42% |
| Lucas De Marchi | 1 | 0.01% | 1 | 0.42% |
| David Brownell | 1 | 0.01% | 1 | 0.42% |
| Total | 8429 | 236 |
/* * gendisk handling */ #include <linux/module.h> #include <linux/fs.h> #include <linux/genhd.h> #include <linux/kdev_t.h> #include <linux/kernel.h> #include <linux/blkdev.h> #include <linux/backing-dev.h> #include <linux/init.h> #include <linux/spinlock.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/slab.h> #include <linux/kmod.h> #include <linux/kobj_map.h> #include <linux/mutex.h> #include <linux/idr.h> #include <linux/log2.h> #include <linux/pm_runtime.h> #include <linux/badblocks.h> #include "blk.h" static DEFINE_MUTEX(block_class_lock); struct kobject *block_depr; /* for extended dynamic devt allocation, currently only one major is used */ #define NR_EXT_DEVT (1 << MINORBITS) /* For extended devt allocation. ext_devt_lock prevents look up * results from going away underneath its user. */ static DEFINE_SPINLOCK(ext_devt_lock); static DEFINE_IDR(ext_devt_idr); static const struct device_type disk_type; 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); void part_inc_in_flight(struct request_queue *q, struct hd_struct *part, int rw) { if (queue_is_mq(q)) return; part_stat_local_inc(part, in_flight[rw]); if (part->partno) part_stat_local_inc(&part_to_disk(part)->part0, in_flight[rw]); } void part_dec_in_flight(struct request_queue *q, struct hd_struct *part, int rw) { if (queue_is_mq(q)) return; part_stat_local_dec(part, in_flight[rw]); if (part->partno) part_stat_local_dec(&part_to_disk(part)->part0, in_flight[rw]); } unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part) { 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); } if ((int)inflight < 0) inflight = 0; return inflight; } void part_in_flight_rw(struct request_queue *q, struct hd_struct *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) { inflight[0] += part_stat_local_read_cpu(part, in_flight[0], cpu); inflight[1] += part_stat_local_read_cpu(part, in_flight[1], cpu); } if ((int)inflight[0] < 0) inflight[0] = 0; if ((int)inflight[1] < 0) 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. * */ #define BLKDEV_MAJOR_HASH_SIZE 255 static struct blk_major_name { struct blk_major_name *next; int major; char name[16]; } *major_names[BLKDEV_MAJOR_HASH_SIZE]; /* index in the above - for now: assume no multimajor ranges */ static inline int major_to_index(unsigned major) { return major % BLKDEV_MAJOR_HASH_SIZE; } #ifdef CONFIG_PROC_FS void blkdev_show(struct seq_file *seqf, off_t offset) { struct blk_major_name *dp; mutex_lock(&block_class_lock); 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); } #endif /* CONFIG_PROC_FS */ /** * 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 * * The @name must be unique within the system. * * The return value depends on the @major input parameter: * * - if a major device number was requested in range [1..BLKDEV_MAJOR_MAX-1] * then the function returns zero on success, or a negative error code * - if any unused major number was requested with @major = 0 parameter * then the return value is the allocated major number in range * [1..BLKDEV_MAJOR_MAX-1] or a negative error code otherwise * * See Documentation/admin-guide/devices.txt for the list of allocated * major numbers. */ int register_blkdev(unsigned int major, const char *name) { struct blk_major_name **n, *p; int index, ret = 0; mutex_lock(&block_class_lock); /* temporary */ if (major == 0) { for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) { if (major_names[index] == NULL) break; } if (index == 0) { printk("register_blkdev: failed to get major for %s\n", name); ret = -EBUSY; goto out; } major = index; ret = major; } if (major >= BLKDEV_MAJOR_MAX) { pr_err("register_blkdev: major requested (%u) is greater than the maximum (%u) for %s\n", major, BLKDEV_MAJOR_MAX-1, name); ret = -EINVAL; goto out; } p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL); if (p == NULL) { ret = -ENOMEM; goto out; } p->major = major; strlcpy(p->name, name, sizeof(p->name)); p->next = NULL; index = major_to_index(major); for (n = &major_names[index]; *n; n = &(*n)->next) { if ((*n)->major == major) break; } if (!*n) *n = p; else ret = -EBUSY; if (ret < 0) { printk("register_blkdev: cannot get major %u for %s\n", major, name); kfree(p); } out: mutex_unlock(&block_class_lock); return ret; } EXPORT_SYMBOL(register_blkdev); void unregister_blkdev(unsigned int major, const char *name) { struct blk_major_name **n; struct blk_major_name *p = NULL; int index = major_to_index(major); mutex_lock(&block_class_lock); for (n = &major_names[index]; *n; n = &(*n)->next) if ((*n)->major == major) break; if (!*n || strcmp((*n)->name, name)) { WARN_ON(1); } else { p = *n; *n = p->next; } mutex_unlock(&block_class_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) { #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; minor ^= low | high; /* clear both bits */ low <<= distance; /* swap the positions */ high >>= distance; minor |= low | high; /* and set */ } #endif return minor; } /** * 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) { 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; } /** * 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) { if (devt == MKDEV(0, 0)) return; 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); } } static char *bdevt_str(dev_t devt, char *buf) { 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; } /* * 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); } EXPORT_SYMBOL(blk_register_region); void blk_unregister_region(dev_t devt, unsigned long range) { kobj_unmap(bdev_map, devt, range); } EXPORT_SYMBOL(blk_unregister_region); static struct kobject *exact_match(dev_t devt, int *partno, void *data) { struct gendisk *p = data; return &disk_to_dev(p)->kobj; } static int exact_lock(dev_t devt, void *data) { struct gendisk *p = data; if (!get_disk_and_module(p)) return -1; return 0; } 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; ddev->parent = parent; dev_set_name(ddev, "%s", disk->disk_name); /* delay uevents, until we scanned partition table */ dev_set_uevent_suppress(ddev, 1); 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; } } /* * avoid probable deadlock caused by allocating memory with * GFP_KERNEL in runtime_resume callback of its all ancestor * devices */ pm_runtime_set_memalloc_noio(ddev, true); disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj); disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj); if (disk->flags & GENHD_FL_HIDDEN) { dev_set_uevent_suppress(ddev, 0); return; } /* 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); err = sysfs_create_link(&ddev->kobj, &disk->queue->backing_dev_info->dev->kobj, "bdi"); WARN_ON(err); } /** * __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) { dev_t devt; int retval; /* minors == 0 indicates to use ext devt from part0 and should * be accompanied with EXT_DEVT flag. Make sure all * parameters make sense. */ WARN_ON(disk->minors && !(disk->major || disk->first_minor)); WARN_ON(!disk->minors && !(disk->flags & (GENHD_FL_EXT_DEVT | GENHD_FL_HIDDEN))); 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); disk_alloc_events(disk); if (disk->flags & GENHD_FL_HIDDEN) { /* * Don't let hidden disks show up in /proc/partitions, * and don't bother scanning for partitions either. */ disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO; disk->flags |= GENHD_FL_NO_PART_SCAN; } else { 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); } register_disk(parent, disk, groups); if (register_queue) blk_register_queue(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. */ WARN_ON_ONCE(!blk_get_queue(disk->queue)); disk_add_events(disk); blk_integrity_add(disk); } void device_add_disk(struct device *parent, struct gendisk *disk, const struct attribute_group **groups) { __device_add_disk(parent, disk, groups, true); } EXPORT_SYMBOL(device_add_disk); void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk) { __device_add_disk(parent, disk, NULL, false); } EXPORT_SYMBOL(device_add_disk_no_queue_reg); void del_gendisk(struct gendisk *disk) { struct disk_part_iter piter; struct hd_struct *part; 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). */ 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); invalidate_partition(disk, 0); bdev_unhash_inode(disk_devt(disk)); set_capacity(disk, 0); disk->flags &= ~GENHD_FL_UP; up_write(&disk->lookup_sem); 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); } if (!(disk->flags & GENHD_FL_HIDDEN)) blk_unregister_region(disk_devt(disk), disk->minors); kobject_put(disk->part0.holder_dir); kobject_put(disk->slave_dir); part_stat_set_all(&disk->part0, 0); disk->part0.stamp = 0; if (!sysfs_deprecated) 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)); } EXPORT_SYMBOL(del_gendisk); /* sysfs access to bad-blocks list. */ static ssize_t disk_badblocks_show(struct device *dev, struct device_attribute *attr, char *page) { struct gendisk *disk = dev_to_disk(dev); if (!disk->bb) return sprintf(page, "\n"); return badblocks_show(disk->bb, page, 0); } static ssize_t disk_badblocks_store(struct device *dev, struct device_attribute *attr, const char *page, size_t len) { struct gendisk *disk = dev_to_disk(dev); if (!disk->bb) return -ENXIO; return badblocks_store(disk->bb, page, len, 0); } /** * get_gendisk - get partitioning information for a given device * @devt: device to get partitioning information for * @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) { 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; 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); } spin_unlock_bh(&ext_devt_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); } #ifdef CONFIG_PROC_FS /* iterator */ static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos) { loff_t skip = *pos; struct class_dev_iter *iter; struct device *dev; iter = kmalloc(sizeof(*iter), GFP_KERNEL); if (!iter) return ERR_PTR(-ENOMEM); seqf->private = iter; class_dev_iter_init(iter, &block_class, NULL, &disk_type); do { dev = class_dev_iter_next(iter); if (!dev) return NULL; } while (skip--); return dev_to_disk(dev); } static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos) { struct device *dev; (*pos)++; dev = class_dev_iter_next(seqf->private); if (dev) return dev_to_disk(dev); return NULL; } static void disk_seqf_stop(struct seq_file *seqf, void *v) { struct class_dev_iter *iter = seqf->private; /* stop is called even after start failed :-( */ if (iter) { class_dev_iter_exit(iter); kfree(iter); seqf->private = NULL; } } static void *show_partition_start(struct seq_file *seqf, loff_t *pos) { void *p; p = disk_seqf_start(seqf, pos); if (!IS_ERR_OR_NULL(p) && !*pos) seq_puts(seqf, "major minor #blocks name\n\n"); return p; } 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]; /* 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) 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); return 0; } static const struct seq_operations partitions_op = { .start = show_partition_start, .next = disk_seqf_next, .stop = disk_seqf_stop, .show = show_partition }; #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); return 0; } subsys_initcall(genhd_device_init); static ssize_t disk_range_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gendisk *disk = dev_to_disk(dev); return sprintf(buf, "%d\n", disk->minors); } static ssize_t disk_ext_range_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gendisk *disk = dev_to_disk(dev); return sprintf(buf, "%d\n", disk_max_parts(disk)); } static ssize_t disk_removable_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gendisk *disk = dev_to_disk(dev); return sprintf(buf, "%d\n", (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0)); } static ssize_t disk_hidden_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gendisk *disk = dev_to_disk(dev); return sprintf(buf, "%d\n", (disk->flags & GENHD_FL_HIDDEN ? 1 : 0)); } static ssize_t disk_ro_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gendisk *disk = dev_to_disk(dev); return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0); } 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); } static ssize_t disk_alignment_offset_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gendisk *disk = dev_to_disk(dev); return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue)); } static ssize_t disk_discard_alignment_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gendisk *disk = dev_to_disk(dev); return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue)); } static DEVICE_ATTR(range, 0444, disk_range_show, NULL); static DEVICE_ATTR(ext_range, 0444, disk_ext_range_show, NULL); static DEVICE_ATTR(removable, 0444, disk_removable_show, NULL); static DEVICE_ATTR(hidden, 0444, disk_hidden_show, NULL); static DEVICE_ATTR(ro, 0444, disk_ro_show, NULL); static DEVICE_ATTR(size, 0444, part_size_show, NULL); static DEVICE_ATTR(alignment_offset, 0444, disk_alignment_offset_show, NULL); static DEVICE_ATTR(discard_alignment, 0444, disk_discard_alignment_show, NULL); 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); #ifdef CONFIG_FAIL_MAKE_REQUEST static struct device_attribute dev_attr_fail = __ATTR(make-it-fail, 0644, part_fail_show, part_fail_store); #endif #ifdef CONFIG_FAIL_IO_TIMEOUT static struct device_attribute dev_attr_fail_timeout = __ATTR(io-timeout-fail, 0644, part_timeout_show, part_timeout_store); #endif static struct attribute *disk_attrs[] = { &dev_attr_range.attr, &dev_attr_ext_range.attr, &dev_attr_removable.attr, &dev_attr_hidden.attr, &dev_attr_ro.attr, &dev_attr_size.attr, &dev_attr_alignment_offset.attr, &dev_attr_discard_alignment.attr, &dev_attr_capability.attr, &dev_attr_stat.attr, &dev_attr_inflight.attr, &dev_attr_badblocks.attr, #ifdef CONFIG_FAIL_MAKE_REQUEST &dev_attr_fail.attr, #endif #ifdef CONFIG_FAIL_IO_TIMEOUT &dev_attr_fail_timeout.attr, #endif NULL }; static umode_t disk_visible(struct kobject *kobj, struct attribute *a, int n) { struct device *dev = container_of(kobj, typeof(*dev), kobj); struct gendisk *disk = dev_to_disk(dev); if (a == &dev_attr_badblocks.attr && !disk->bb) return 0; return a->mode; } static struct attribute_group disk_attr_group = { .attrs = disk_attrs, .is_visible = disk_visible, }; static const struct attribute_group *disk_attr_groups[] = { &disk_attr_group, 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 * * 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; size_t size; /* * 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; size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]); new_ptbl = kzalloc_node(size, 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; } static void disk_release(struct device *dev) { 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); } struct class block_class = { .name = "block", }; static char *block_devnode(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); return NULL; } static const struct device_type disk_type = { .name = "disk", .groups = disk_attr_groups, .release = disk_release, .devnode = block_devnode, }; #ifdef CONFIG_PROC_FS /* * aggregate disk stat collector. Uses the same stats that the sysfs * entries do, above, but makes them available through one seq_file. * * The output looks suspiciously like /proc/partitions with a bunch of * extra fields. */ 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]; unsigned int inflight; /* if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next) seq_puts(seqf, "major minor name" " rio rmerge rsect ruse wio wmerge " "wsect wuse running use aveq" "\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 " "%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), 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) ); } disk_part_iter_exit(&piter); return 0; } static const struct seq_operations diskstats_op = { .start = disk_seqf_start, .next = disk_seqf_next, .stop = disk_seqf_stop, .show = diskstats_show }; static int __init proc_genhd_init(void) { proc_create_seq("diskstats", 0, NULL, &diskstats_op); proc_create_seq("partitions", 0, NULL, &partitions_op); return 0; } module_init(proc_genhd_init); #endif /* CONFIG_PROC_FS */ dev_t blk_lookup_devt(const char *name, int 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; if (strcmp(dev_name(dev), name)) continue; 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 *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; } 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)); } return disk; } EXPORT_SYMBOL(__alloc_disk_node); struct kobject *get_disk_and_module(struct gendisk *disk) { struct module *owner; struct kobject *kobj; if (!disk->fops) return NULL; owner = disk->fops->owner; if (owner && !try_module_get(owner)) return NULL; kobj = kobject_get_unless_zero(&disk_to_dev(disk)->kobj); if (kobj == NULL) { module_put(owner); return NULL; } return kobj; } EXPORT_SYMBOL(get_disk_and_module); void put_disk(struct gendisk *disk) { if (disk) kobject_put(&disk_to_dev(disk)->kobj); } 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"; char *envp[] = { event, NULL }; if (!ro) event[8] = '0'; 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 iff there are events which * can't be monitored asynchronously. */ if (ev->poll_msecs >= 0) intv_msecs = ev->poll_msecs; else if (disk->events & ~disk->async_events) 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. Unlisted events are processed the * same internally but never get reported to userland. */ for (i = 0; i < ARRAY_SIZE(disk_uevents); i++) if (events & disk->events & (1 << i)) 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. * * events : list of all supported events * events_async : list of events which can be detected w/o polling * events_poll_msecs : polling interval, 0: disable, -1: system default */ static ssize_t __disk_events_show(unsigned int events, char *buf) { 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); return __disk_events_show(disk->events, buf); } static ssize_t disk_events_async_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gendisk *disk = dev_to_disk(dev); return __disk_events_show(disk->async_events, buf); } static ssize_t disk_events_poll_msecs_show(struct device *dev, struct device_attribute *attr, char *buf) { struct gendisk *disk = dev_to_disk(dev); 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; 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/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) 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) { if (!disk->ev) return; /* 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); 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) return; disk_block_events(disk); mutex_lock(&disk_events_mutex); list_del_init(&disk->ev->node); mutex_unlock(&disk_events_mutex); sysfs_remove_files(&disk_to_dev(disk)->kobj, disk_events_attrs); } static void disk_release_events(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); }
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