![Randy Dunlap](/assets/img/avatar_default.png)
Fix block kernel-doc warnings: Warning(linux-2.6.27-git4//fs/block_dev.c:1272): No description found for parameter 'path' Warning(linux-2.6.27-git4//block/blk-core.c:1021): No description found for parameter 'cpu' Warning(linux-2.6.27-git4//block/blk-core.c:1021): No description found for parameter 'part' Warning(/var/linsrc/linux-2.6.27-git4//block/genhd.c:544): No description found for parameter 'partno' Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
1162 lines
26 KiB
C
1162 lines
26 KiB
C
/*
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* gendisk handling
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*/
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/genhd.h>
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#include <linux/kdev_t.h>
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#include <linux/kernel.h>
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#include <linux/blkdev.h>
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#include <linux/init.h>
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#include <linux/spinlock.h>
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#include <linux/seq_file.h>
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#include <linux/slab.h>
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#include <linux/kmod.h>
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#include <linux/kobj_map.h>
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#include <linux/buffer_head.h>
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#include <linux/mutex.h>
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#include <linux/idr.h>
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#include "blk.h"
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static DEFINE_MUTEX(block_class_lock);
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#ifndef CONFIG_SYSFS_DEPRECATED
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struct kobject *block_depr;
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#endif
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/* for extended dynamic devt allocation, currently only one major is used */
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#define MAX_EXT_DEVT (1 << MINORBITS)
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/* For extended devt allocation. ext_devt_mutex prevents look up
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* results from going away underneath its user.
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*/
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static DEFINE_MUTEX(ext_devt_mutex);
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static DEFINE_IDR(ext_devt_idr);
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static struct device_type disk_type;
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/**
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* disk_get_part - get partition
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* @disk: disk to look partition from
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* @partno: partition number
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*
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* Look for partition @partno from @disk. If found, increment
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* reference count and return it.
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*
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* CONTEXT:
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* Don't care.
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*
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* RETURNS:
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* Pointer to the found partition on success, NULL if not found.
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*/
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struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
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{
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struct hd_struct *part = NULL;
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struct disk_part_tbl *ptbl;
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if (unlikely(partno < 0))
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return NULL;
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rcu_read_lock();
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ptbl = rcu_dereference(disk->part_tbl);
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if (likely(partno < ptbl->len)) {
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part = rcu_dereference(ptbl->part[partno]);
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if (part)
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get_device(part_to_dev(part));
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}
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rcu_read_unlock();
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return part;
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}
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EXPORT_SYMBOL_GPL(disk_get_part);
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/**
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* disk_part_iter_init - initialize partition iterator
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* @piter: iterator to initialize
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* @disk: disk to iterate over
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* @flags: DISK_PITER_* flags
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*
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* Initialize @piter so that it iterates over partitions of @disk.
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*
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* CONTEXT:
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* Don't care.
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*/
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void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk,
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unsigned int flags)
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{
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struct disk_part_tbl *ptbl;
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rcu_read_lock();
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ptbl = rcu_dereference(disk->part_tbl);
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piter->disk = disk;
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piter->part = NULL;
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if (flags & DISK_PITER_REVERSE)
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piter->idx = ptbl->len - 1;
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else if (flags & DISK_PITER_INCL_PART0)
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piter->idx = 0;
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else
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piter->idx = 1;
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piter->flags = flags;
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rcu_read_unlock();
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}
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EXPORT_SYMBOL_GPL(disk_part_iter_init);
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/**
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* disk_part_iter_next - proceed iterator to the next partition and return it
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* @piter: iterator of interest
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*
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* Proceed @piter to the next partition and return it.
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*
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* CONTEXT:
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* Don't care.
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*/
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struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter)
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{
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struct disk_part_tbl *ptbl;
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int inc, end;
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/* put the last partition */
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disk_put_part(piter->part);
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piter->part = NULL;
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/* get part_tbl */
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rcu_read_lock();
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ptbl = rcu_dereference(piter->disk->part_tbl);
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/* determine iteration parameters */
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if (piter->flags & DISK_PITER_REVERSE) {
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inc = -1;
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if (piter->flags & DISK_PITER_INCL_PART0)
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end = -1;
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else
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end = 0;
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} else {
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inc = 1;
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end = ptbl->len;
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}
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/* iterate to the next partition */
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for (; piter->idx != end; piter->idx += inc) {
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struct hd_struct *part;
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part = rcu_dereference(ptbl->part[piter->idx]);
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if (!part)
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continue;
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if (!(piter->flags & DISK_PITER_INCL_EMPTY) && !part->nr_sects)
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continue;
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get_device(part_to_dev(part));
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piter->part = part;
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piter->idx += inc;
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break;
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}
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rcu_read_unlock();
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return piter->part;
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}
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EXPORT_SYMBOL_GPL(disk_part_iter_next);
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/**
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* disk_part_iter_exit - finish up partition iteration
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* @piter: iter of interest
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*
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* Called when iteration is over. Cleans up @piter.
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*
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* CONTEXT:
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* Don't care.
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*/
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void disk_part_iter_exit(struct disk_part_iter *piter)
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{
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disk_put_part(piter->part);
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piter->part = NULL;
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}
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EXPORT_SYMBOL_GPL(disk_part_iter_exit);
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/**
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* disk_map_sector_rcu - map sector to partition
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* @disk: gendisk of interest
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* @sector: sector to map
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*
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* Find out which partition @sector maps to on @disk. This is
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* primarily used for stats accounting.
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*
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* CONTEXT:
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* RCU read locked. The returned partition pointer is valid only
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* while preemption is disabled.
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*
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* RETURNS:
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* Found partition on success, part0 is returned if no partition matches
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*/
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struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
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{
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struct disk_part_tbl *ptbl;
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int i;
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ptbl = rcu_dereference(disk->part_tbl);
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for (i = 1; i < ptbl->len; i++) {
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struct hd_struct *part = rcu_dereference(ptbl->part[i]);
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if (part && part->start_sect <= sector &&
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sector < part->start_sect + part->nr_sects)
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return part;
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}
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return &disk->part0;
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}
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EXPORT_SYMBOL_GPL(disk_map_sector_rcu);
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/*
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* Can be deleted altogether. Later.
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*
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*/
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static struct blk_major_name {
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struct blk_major_name *next;
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int major;
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char name[16];
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} *major_names[BLKDEV_MAJOR_HASH_SIZE];
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/* index in the above - for now: assume no multimajor ranges */
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static inline int major_to_index(int major)
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{
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return major % BLKDEV_MAJOR_HASH_SIZE;
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}
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#ifdef CONFIG_PROC_FS
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void blkdev_show(struct seq_file *seqf, off_t offset)
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{
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struct blk_major_name *dp;
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if (offset < BLKDEV_MAJOR_HASH_SIZE) {
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mutex_lock(&block_class_lock);
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for (dp = major_names[offset]; dp; dp = dp->next)
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seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
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mutex_unlock(&block_class_lock);
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}
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}
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#endif /* CONFIG_PROC_FS */
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int register_blkdev(unsigned int major, const char *name)
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{
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struct blk_major_name **n, *p;
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int index, ret = 0;
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mutex_lock(&block_class_lock);
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/* temporary */
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if (major == 0) {
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for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
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if (major_names[index] == NULL)
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break;
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}
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if (index == 0) {
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printk("register_blkdev: failed to get major for %s\n",
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name);
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ret = -EBUSY;
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goto out;
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}
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major = index;
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ret = major;
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}
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p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
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if (p == NULL) {
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ret = -ENOMEM;
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goto out;
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}
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p->major = major;
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strlcpy(p->name, name, sizeof(p->name));
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p->next = NULL;
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index = major_to_index(major);
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for (n = &major_names[index]; *n; n = &(*n)->next) {
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if ((*n)->major == major)
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break;
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}
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if (!*n)
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*n = p;
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else
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ret = -EBUSY;
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if (ret < 0) {
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printk("register_blkdev: cannot get major %d for %s\n",
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major, name);
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kfree(p);
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}
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out:
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mutex_unlock(&block_class_lock);
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return ret;
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}
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EXPORT_SYMBOL(register_blkdev);
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void unregister_blkdev(unsigned int major, const char *name)
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{
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struct blk_major_name **n;
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struct blk_major_name *p = NULL;
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int index = major_to_index(major);
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mutex_lock(&block_class_lock);
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for (n = &major_names[index]; *n; n = &(*n)->next)
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if ((*n)->major == major)
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break;
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if (!*n || strcmp((*n)->name, name)) {
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WARN_ON(1);
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} else {
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p = *n;
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*n = p->next;
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}
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mutex_unlock(&block_class_lock);
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kfree(p);
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}
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EXPORT_SYMBOL(unregister_blkdev);
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static struct kobj_map *bdev_map;
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/**
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* blk_mangle_minor - scatter minor numbers apart
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* @minor: minor number to mangle
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*
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* Scatter consecutively allocated @minor number apart if MANGLE_DEVT
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* is enabled. Mangling twice gives the original value.
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*
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* RETURNS:
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* Mangled value.
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*
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* CONTEXT:
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* Don't care.
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*/
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static int blk_mangle_minor(int minor)
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{
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#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
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int i;
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for (i = 0; i < MINORBITS / 2; i++) {
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int low = minor & (1 << i);
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int high = minor & (1 << (MINORBITS - 1 - i));
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int distance = MINORBITS - 1 - 2 * i;
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minor ^= low | high; /* clear both bits */
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low <<= distance; /* swap the positions */
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high >>= distance;
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minor |= low | high; /* and set */
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}
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#endif
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return minor;
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}
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/**
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* blk_alloc_devt - allocate a dev_t for a partition
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* @part: partition to allocate dev_t for
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* @devt: out parameter for resulting dev_t
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*
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* Allocate a dev_t for block device.
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*
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* RETURNS:
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* 0 on success, allocated dev_t is returned in *@devt. -errno on
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* failure.
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*
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* CONTEXT:
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* Might sleep.
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*/
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int blk_alloc_devt(struct hd_struct *part, dev_t *devt)
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{
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struct gendisk *disk = part_to_disk(part);
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int idx, rc;
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/* in consecutive minor range? */
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if (part->partno < disk->minors) {
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*devt = MKDEV(disk->major, disk->first_minor + part->partno);
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return 0;
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}
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/* allocate ext devt */
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do {
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if (!idr_pre_get(&ext_devt_idr, GFP_KERNEL))
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return -ENOMEM;
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rc = idr_get_new(&ext_devt_idr, part, &idx);
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} while (rc == -EAGAIN);
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if (rc)
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return rc;
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if (idx > MAX_EXT_DEVT) {
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idr_remove(&ext_devt_idr, idx);
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return -EBUSY;
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}
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*devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx));
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return 0;
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}
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/**
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* blk_free_devt - free a dev_t
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* @devt: dev_t to free
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*
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* Free @devt which was allocated using blk_alloc_devt().
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*
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* CONTEXT:
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* Might sleep.
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*/
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void blk_free_devt(dev_t devt)
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{
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might_sleep();
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if (devt == MKDEV(0, 0))
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return;
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if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
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mutex_lock(&ext_devt_mutex);
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idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
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mutex_unlock(&ext_devt_mutex);
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}
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}
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static char *bdevt_str(dev_t devt, char *buf)
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{
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if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) {
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char tbuf[BDEVT_SIZE];
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snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt));
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snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);
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} else
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snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
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return buf;
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}
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/*
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* Register device numbers dev..(dev+range-1)
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* range must be nonzero
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* The hash chain is sorted on range, so that subranges can override.
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*/
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void blk_register_region(dev_t devt, unsigned long range, struct module *module,
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struct kobject *(*probe)(dev_t, int *, void *),
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int (*lock)(dev_t, void *), void *data)
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{
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kobj_map(bdev_map, devt, range, module, probe, lock, data);
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}
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EXPORT_SYMBOL(blk_register_region);
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void blk_unregister_region(dev_t devt, unsigned long range)
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{
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kobj_unmap(bdev_map, devt, range);
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}
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EXPORT_SYMBOL(blk_unregister_region);
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static struct kobject *exact_match(dev_t devt, int *partno, void *data)
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{
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struct gendisk *p = data;
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return &disk_to_dev(p)->kobj;
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}
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static int exact_lock(dev_t devt, void *data)
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{
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struct gendisk *p = data;
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if (!get_disk(p))
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return -1;
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return 0;
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}
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/**
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* add_disk - add partitioning information to kernel list
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* @disk: per-device partitioning information
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*
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* This function registers the partitioning information in @disk
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* with the kernel.
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*
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* FIXME: error handling
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*/
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void add_disk(struct gendisk *disk)
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{
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struct backing_dev_info *bdi;
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dev_t devt;
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int retval;
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/* minors == 0 indicates to use ext devt from part0 and should
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* be accompanied with EXT_DEVT flag. Make sure all
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* parameters make sense.
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*/
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WARN_ON(disk->minors && !(disk->major || disk->first_minor));
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WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT));
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disk->flags |= GENHD_FL_UP;
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retval = blk_alloc_devt(&disk->part0, &devt);
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if (retval) {
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WARN_ON(1);
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return;
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}
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disk_to_dev(disk)->devt = devt;
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/* ->major and ->first_minor aren't supposed to be
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* dereferenced from here on, but set them just in case.
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*/
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disk->major = MAJOR(devt);
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disk->first_minor = MINOR(devt);
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blk_register_region(disk_devt(disk), disk->minors, NULL,
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exact_match, exact_lock, disk);
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register_disk(disk);
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blk_register_queue(disk);
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bdi = &disk->queue->backing_dev_info;
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bdi_register_dev(bdi, disk_devt(disk));
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retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
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"bdi");
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WARN_ON(retval);
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}
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EXPORT_SYMBOL(add_disk);
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EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */
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void unlink_gendisk(struct gendisk *disk)
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{
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sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
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bdi_unregister(&disk->queue->backing_dev_info);
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blk_unregister_queue(disk);
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blk_unregister_region(disk_devt(disk), disk->minors);
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}
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|
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/**
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* get_gendisk - get partitioning information for a given device
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* @devt: device to get partitioning information for
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* @partno: returned partition index
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*
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* 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;
|
|
|
|
mutex_lock(&ext_devt_mutex);
|
|
part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
|
|
if (part && get_disk(part_to_disk(part))) {
|
|
*partno = part->partno;
|
|
disk = part_to_disk(part);
|
|
}
|
|
mutex_unlock(&ext_devt_mutex);
|
|
}
|
|
|
|
return disk;
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
* surpressed
|
|
*/
|
|
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", is_part0 ? "" : " ",
|
|
bdevt_str(part_devt(part), devt_buf),
|
|
(unsigned long long)part->nr_sects >> 1,
|
|
disk_name(disk, part->partno, name_buf));
|
|
if (is_part0) {
|
|
if (disk->driverfs_dev != NULL &&
|
|
disk->driverfs_dev->driver != NULL)
|
|
printk(" driver: %s\n",
|
|
disk->driverfs_dev->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);
|
|
}
|
|
}
|
|
|
|
static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
|
|
{
|
|
static void *p;
|
|
|
|
p = disk_seqf_start(seqf, pos);
|
|
if (!IS_ERR(p) && 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_partitionable(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 >> 1,
|
|
disk_name(sgp, part->partno, buf));
|
|
disk_part_iter_exit(&piter);
|
|
|
|
return 0;
|
|
}
|
|
|
|
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();
|
|
|
|
#ifndef CONFIG_SYSFS_DEPRECATED
|
|
/* create top-level block dir */
|
|
block_depr = kobject_create_and_add("block", NULL);
|
|
#endif
|
|
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_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 DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
|
|
static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
|
|
static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
|
|
static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
|
|
static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
|
|
static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
|
|
static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
|
|
#ifdef CONFIG_FAIL_MAKE_REQUEST
|
|
static struct device_attribute dev_attr_fail =
|
|
__ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
|
|
#endif
|
|
#ifdef CONFIG_FAIL_IO_TIMEOUT
|
|
static struct device_attribute dev_attr_fail_timeout =
|
|
__ATTR(io-timeout-fail, S_IRUGO|S_IWUSR, 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_ro.attr,
|
|
&dev_attr_size.attr,
|
|
&dev_attr_capability.attr,
|
|
&dev_attr_stat.attr,
|
|
#ifdef CONFIG_FAIL_MAKE_REQUEST
|
|
&dev_attr_fail.attr,
|
|
#endif
|
|
#ifdef CONFIG_FAIL_IO_TIMEOUT
|
|
&dev_attr_fail_timeout.attr,
|
|
#endif
|
|
NULL
|
|
};
|
|
|
|
static struct attribute_group disk_attr_group = {
|
|
.attrs = disk_attrs,
|
|
};
|
|
|
|
static struct attribute_group *disk_attr_groups[] = {
|
|
&disk_attr_group,
|
|
NULL
|
|
};
|
|
|
|
static void disk_free_ptbl_rcu_cb(struct rcu_head *head)
|
|
{
|
|
struct disk_part_tbl *ptbl =
|
|
container_of(head, struct disk_part_tbl, rcu_head);
|
|
|
|
kfree(ptbl);
|
|
}
|
|
|
|
/**
|
|
* 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_mutx locked.
|
|
*/
|
|
static void disk_replace_part_tbl(struct gendisk *disk,
|
|
struct disk_part_tbl *new_ptbl)
|
|
{
|
|
struct disk_part_tbl *old_ptbl = disk->part_tbl;
|
|
|
|
rcu_assign_pointer(disk->part_tbl, new_ptbl);
|
|
if (old_ptbl)
|
|
call_rcu(&old_ptbl->rcu_head, disk_free_ptbl_rcu_cb);
|
|
}
|
|
|
|
/**
|
|
* 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, 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 = disk->part_tbl;
|
|
struct disk_part_tbl *new_ptbl;
|
|
int len = old_ptbl ? old_ptbl->len : 0;
|
|
int target = partno + 1;
|
|
size_t size;
|
|
int i;
|
|
|
|
/* 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;
|
|
|
|
INIT_RCU_HEAD(&new_ptbl->rcu_head);
|
|
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);
|
|
|
|
kfree(disk->random);
|
|
disk_replace_part_tbl(disk, NULL);
|
|
free_part_stats(&disk->part0);
|
|
kfree(disk);
|
|
}
|
|
struct class block_class = {
|
|
.name = "block",
|
|
};
|
|
|
|
static struct device_type disk_type = {
|
|
.name = "disk",
|
|
.groups = disk_attr_groups,
|
|
.release = disk_release,
|
|
};
|
|
|
|
#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];
|
|
int cpu;
|
|
|
|
/*
|
|
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_PART0);
|
|
while ((hd = disk_part_iter_next(&piter))) {
|
|
cpu = part_stat_lock();
|
|
part_round_stats(cpu, hd);
|
|
part_stat_unlock();
|
|
seq_printf(seqf, "%4d %7d %s %lu %lu %llu "
|
|
"%u %lu %lu %llu %u %u %u %u\n",
|
|
MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
|
|
disk_name(gp, hd->partno, buf),
|
|
part_stat_read(hd, ios[0]),
|
|
part_stat_read(hd, merges[0]),
|
|
(unsigned long long)part_stat_read(hd, sectors[0]),
|
|
jiffies_to_msecs(part_stat_read(hd, ticks[0])),
|
|
part_stat_read(hd, ios[1]),
|
|
part_stat_read(hd, merges[1]),
|
|
(unsigned long long)part_stat_read(hd, sectors[1]),
|
|
jiffies_to_msecs(part_stat_read(hd, ticks[1])),
|
|
hd->in_flight,
|
|
jiffies_to_msecs(part_stat_read(hd, io_ticks)),
|
|
jiffies_to_msecs(part_stat_read(hd, time_in_queue))
|
|
);
|
|
}
|
|
disk_part_iter_exit(&piter);
|
|
|
|
return 0;
|
|
}
|
|
|
|
const struct seq_operations diskstats_op = {
|
|
.start = disk_seqf_start,
|
|
.next = disk_seqf_next,
|
|
.stop = disk_seqf_stop,
|
|
.show = diskstats_show
|
|
};
|
|
#endif /* CONFIG_PROC_FS */
|
|
|
|
static void media_change_notify_thread(struct work_struct *work)
|
|
{
|
|
struct gendisk *gd = container_of(work, struct gendisk, async_notify);
|
|
char event[] = "MEDIA_CHANGE=1";
|
|
char *envp[] = { event, NULL };
|
|
|
|
/*
|
|
* set enviroment vars to indicate which event this is for
|
|
* so that user space will know to go check the media status.
|
|
*/
|
|
kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
|
|
put_device(gd->driverfs_dev);
|
|
}
|
|
|
|
#if 0
|
|
void genhd_media_change_notify(struct gendisk *disk)
|
|
{
|
|
get_device(disk->driverfs_dev);
|
|
schedule_work(&disk->async_notify);
|
|
}
|
|
EXPORT_SYMBOL_GPL(genhd_media_change_notify);
|
|
#endif /* 0 */
|
|
|
|
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->bus_id, name))
|
|
continue;
|
|
|
|
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(int minors)
|
|
{
|
|
return alloc_disk_node(minors, -1);
|
|
}
|
|
EXPORT_SYMBOL(alloc_disk);
|
|
|
|
struct gendisk *alloc_disk_node(int minors, int node_id)
|
|
{
|
|
struct gendisk *disk;
|
|
|
|
disk = kmalloc_node(sizeof(struct gendisk),
|
|
GFP_KERNEL | __GFP_ZERO, node_id);
|
|
if (disk) {
|
|
if (!init_part_stats(&disk->part0)) {
|
|
kfree(disk);
|
|
return NULL;
|
|
}
|
|
if (disk_expand_part_tbl(disk, 0)) {
|
|
free_part_stats(&disk->part0);
|
|
kfree(disk);
|
|
return NULL;
|
|
}
|
|
disk->part_tbl->part[0] = &disk->part0;
|
|
|
|
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));
|
|
INIT_WORK(&disk->async_notify,
|
|
media_change_notify_thread);
|
|
disk->node_id = node_id;
|
|
}
|
|
return disk;
|
|
}
|
|
EXPORT_SYMBOL(alloc_disk_node);
|
|
|
|
struct kobject *get_disk(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(&disk_to_dev(disk)->kobj);
|
|
if (kobj == NULL) {
|
|
module_put(owner);
|
|
return NULL;
|
|
}
|
|
return kobj;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL(get_disk);
|
|
|
|
void put_disk(struct gendisk *disk)
|
|
{
|
|
if (disk)
|
|
kobject_put(&disk_to_dev(disk)->kobj);
|
|
}
|
|
|
|
EXPORT_SYMBOL(put_disk);
|
|
|
|
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;
|
|
|
|
disk_part_iter_init(&piter, disk,
|
|
DISK_PITER_INCL_EMPTY | DISK_PITER_INCL_PART0);
|
|
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);
|
|
bdput(bdev);
|
|
}
|
|
return res;
|
|
}
|
|
|
|
EXPORT_SYMBOL(invalidate_partition);
|