![weiping zhang](/assets/img/avatar_default.png)
put_device(pdev) will call pdev->type->release finally, and blk_free_devt has been called in part_release(), so remove it. Signed-off-by: weiping zhang <zhangweiping@didichuxing.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
664 lines
17 KiB
C
664 lines
17 KiB
C
/*
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* Code extracted from drivers/block/genhd.c
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* Copyright (C) 1991-1998 Linus Torvalds
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* Re-organised Feb 1998 Russell King
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*
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* We now have independent partition support from the
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* block drivers, which allows all the partition code to
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* be grouped in one location, and it to be mostly self
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* contained.
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*/
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/slab.h>
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#include <linux/kmod.h>
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#include <linux/ctype.h>
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#include <linux/genhd.h>
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#include <linux/blktrace_api.h>
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#include "partitions/check.h"
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#ifdef CONFIG_BLK_DEV_MD
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extern void md_autodetect_dev(dev_t dev);
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#endif
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/*
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* disk_name() is used by partition check code and the genhd driver.
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* It formats the devicename of the indicated disk into
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* the supplied buffer (of size at least 32), and returns
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* a pointer to that same buffer (for convenience).
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*/
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char *disk_name(struct gendisk *hd, int partno, char *buf)
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{
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if (!partno)
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snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
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else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
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snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, partno);
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else
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snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, partno);
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return buf;
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}
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const char *bdevname(struct block_device *bdev, char *buf)
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{
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return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf);
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}
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EXPORT_SYMBOL(bdevname);
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/*
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* There's very little reason to use this, you should really
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* have a struct block_device just about everywhere and use
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* bdevname() instead.
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*/
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const char *__bdevname(dev_t dev, char *buffer)
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{
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scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
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MAJOR(dev), MINOR(dev));
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return buffer;
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}
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EXPORT_SYMBOL(__bdevname);
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static ssize_t part_partition_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct hd_struct *p = dev_to_part(dev);
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return sprintf(buf, "%d\n", p->partno);
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}
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static ssize_t part_start_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct hd_struct *p = dev_to_part(dev);
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return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
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}
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ssize_t part_size_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct hd_struct *p = dev_to_part(dev);
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return sprintf(buf, "%llu\n",(unsigned long long)part_nr_sects_read(p));
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}
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static ssize_t part_ro_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct hd_struct *p = dev_to_part(dev);
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return sprintf(buf, "%d\n", p->policy ? 1 : 0);
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}
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static ssize_t part_alignment_offset_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct hd_struct *p = dev_to_part(dev);
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return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
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}
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static ssize_t part_discard_alignment_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct hd_struct *p = dev_to_part(dev);
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return sprintf(buf, "%u\n", p->discard_alignment);
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}
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ssize_t part_stat_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct hd_struct *p = dev_to_part(dev);
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struct request_queue *q = dev_to_disk(dev)->queue;
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unsigned int inflight[2];
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int cpu;
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cpu = part_stat_lock();
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part_round_stats(q, cpu, p);
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part_stat_unlock();
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part_in_flight(q, p, inflight);
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return sprintf(buf,
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"%8lu %8lu %8llu %8u "
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"%8lu %8lu %8llu %8u "
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"%8u %8u %8u"
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"\n",
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part_stat_read(p, ios[READ]),
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part_stat_read(p, merges[READ]),
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(unsigned long long)part_stat_read(p, sectors[READ]),
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jiffies_to_msecs(part_stat_read(p, ticks[READ])),
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part_stat_read(p, ios[WRITE]),
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part_stat_read(p, merges[WRITE]),
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(unsigned long long)part_stat_read(p, sectors[WRITE]),
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jiffies_to_msecs(part_stat_read(p, ticks[WRITE])),
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inflight[0],
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jiffies_to_msecs(part_stat_read(p, io_ticks)),
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jiffies_to_msecs(part_stat_read(p, time_in_queue)));
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}
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ssize_t part_inflight_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct hd_struct *p = dev_to_part(dev);
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return sprintf(buf, "%8u %8u\n", atomic_read(&p->in_flight[0]),
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atomic_read(&p->in_flight[1]));
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}
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#ifdef CONFIG_FAIL_MAKE_REQUEST
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ssize_t part_fail_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct hd_struct *p = dev_to_part(dev);
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return sprintf(buf, "%d\n", p->make_it_fail);
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}
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ssize_t part_fail_store(struct device *dev,
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struct device_attribute *attr,
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const char *buf, size_t count)
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{
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struct hd_struct *p = dev_to_part(dev);
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int i;
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if (count > 0 && sscanf(buf, "%d", &i) > 0)
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p->make_it_fail = (i == 0) ? 0 : 1;
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return count;
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}
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#endif
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static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
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static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
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static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
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static DEVICE_ATTR(ro, S_IRUGO, part_ro_show, NULL);
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static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL);
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static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show,
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NULL);
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static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
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static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
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#ifdef CONFIG_FAIL_MAKE_REQUEST
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static struct device_attribute dev_attr_fail =
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__ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
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#endif
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static struct attribute *part_attrs[] = {
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&dev_attr_partition.attr,
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&dev_attr_start.attr,
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&dev_attr_size.attr,
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&dev_attr_ro.attr,
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&dev_attr_alignment_offset.attr,
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&dev_attr_discard_alignment.attr,
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&dev_attr_stat.attr,
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&dev_attr_inflight.attr,
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#ifdef CONFIG_FAIL_MAKE_REQUEST
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&dev_attr_fail.attr,
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#endif
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NULL
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};
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static struct attribute_group part_attr_group = {
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.attrs = part_attrs,
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};
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static const struct attribute_group *part_attr_groups[] = {
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&part_attr_group,
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#ifdef CONFIG_BLK_DEV_IO_TRACE
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&blk_trace_attr_group,
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#endif
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NULL
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};
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static void part_release(struct device *dev)
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{
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struct hd_struct *p = dev_to_part(dev);
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blk_free_devt(dev->devt);
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hd_free_part(p);
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kfree(p);
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}
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static int part_uevent(struct device *dev, struct kobj_uevent_env *env)
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{
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struct hd_struct *part = dev_to_part(dev);
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add_uevent_var(env, "PARTN=%u", part->partno);
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if (part->info && part->info->volname[0])
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add_uevent_var(env, "PARTNAME=%s", part->info->volname);
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return 0;
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}
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struct device_type part_type = {
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.name = "partition",
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.groups = part_attr_groups,
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.release = part_release,
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.uevent = part_uevent,
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};
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static void delete_partition_rcu_cb(struct rcu_head *head)
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{
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struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
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part->start_sect = 0;
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part->nr_sects = 0;
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part_stat_set_all(part, 0);
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put_device(part_to_dev(part));
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}
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void __delete_partition(struct percpu_ref *ref)
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{
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struct hd_struct *part = container_of(ref, struct hd_struct, ref);
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call_rcu(&part->rcu_head, delete_partition_rcu_cb);
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}
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/*
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* Must be called either with bd_mutex held, before a disk can be opened or
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* after all disk users are gone.
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*/
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void delete_partition(struct gendisk *disk, int partno)
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{
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struct disk_part_tbl *ptbl =
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rcu_dereference_protected(disk->part_tbl, 1);
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struct hd_struct *part;
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if (partno >= ptbl->len)
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return;
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part = rcu_dereference_protected(ptbl->part[partno], 1);
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if (!part)
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return;
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rcu_assign_pointer(ptbl->part[partno], NULL);
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rcu_assign_pointer(ptbl->last_lookup, NULL);
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kobject_put(part->holder_dir);
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device_del(part_to_dev(part));
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hd_struct_kill(part);
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}
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static ssize_t whole_disk_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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return 0;
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}
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static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
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whole_disk_show, NULL);
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/*
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* Must be called either with bd_mutex held, before a disk can be opened or
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* after all disk users are gone.
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*/
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struct hd_struct *add_partition(struct gendisk *disk, int partno,
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sector_t start, sector_t len, int flags,
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struct partition_meta_info *info)
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{
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struct hd_struct *p;
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dev_t devt = MKDEV(0, 0);
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struct device *ddev = disk_to_dev(disk);
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struct device *pdev;
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struct disk_part_tbl *ptbl;
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const char *dname;
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int err;
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err = disk_expand_part_tbl(disk, partno);
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if (err)
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return ERR_PTR(err);
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ptbl = rcu_dereference_protected(disk->part_tbl, 1);
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if (ptbl->part[partno])
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return ERR_PTR(-EBUSY);
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p = kzalloc(sizeof(*p), GFP_KERNEL);
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if (!p)
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return ERR_PTR(-EBUSY);
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if (!init_part_stats(p)) {
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err = -ENOMEM;
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goto out_free;
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}
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seqcount_init(&p->nr_sects_seq);
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pdev = part_to_dev(p);
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p->start_sect = start;
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p->alignment_offset =
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queue_limit_alignment_offset(&disk->queue->limits, start);
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p->discard_alignment =
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queue_limit_discard_alignment(&disk->queue->limits, start);
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p->nr_sects = len;
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p->partno = partno;
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p->policy = get_disk_ro(disk);
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if (info) {
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struct partition_meta_info *pinfo = alloc_part_info(disk);
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if (!pinfo) {
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err = -ENOMEM;
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goto out_free_stats;
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}
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memcpy(pinfo, info, sizeof(*info));
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p->info = pinfo;
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}
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dname = dev_name(ddev);
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if (isdigit(dname[strlen(dname) - 1]))
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dev_set_name(pdev, "%sp%d", dname, partno);
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else
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dev_set_name(pdev, "%s%d", dname, partno);
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device_initialize(pdev);
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pdev->class = &block_class;
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pdev->type = &part_type;
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pdev->parent = ddev;
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err = blk_alloc_devt(p, &devt);
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if (err)
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goto out_free_info;
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pdev->devt = devt;
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/* delay uevent until 'holders' subdir is created */
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dev_set_uevent_suppress(pdev, 1);
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err = device_add(pdev);
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if (err)
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goto out_put;
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err = -ENOMEM;
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p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
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if (!p->holder_dir)
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goto out_del;
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dev_set_uevent_suppress(pdev, 0);
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if (flags & ADDPART_FLAG_WHOLEDISK) {
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err = device_create_file(pdev, &dev_attr_whole_disk);
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if (err)
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goto out_del;
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}
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err = hd_ref_init(p);
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if (err) {
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if (flags & ADDPART_FLAG_WHOLEDISK)
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goto out_remove_file;
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goto out_del;
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}
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/* everything is up and running, commence */
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rcu_assign_pointer(ptbl->part[partno], p);
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/* suppress uevent if the disk suppresses it */
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if (!dev_get_uevent_suppress(ddev))
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kobject_uevent(&pdev->kobj, KOBJ_ADD);
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return p;
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out_free_info:
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free_part_info(p);
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out_free_stats:
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free_part_stats(p);
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out_free:
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kfree(p);
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return ERR_PTR(err);
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out_remove_file:
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device_remove_file(pdev, &dev_attr_whole_disk);
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out_del:
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kobject_put(p->holder_dir);
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device_del(pdev);
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out_put:
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put_device(pdev);
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return ERR_PTR(err);
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}
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|
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static bool disk_unlock_native_capacity(struct gendisk *disk)
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{
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const struct block_device_operations *bdops = disk->fops;
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|
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if (bdops->unlock_native_capacity &&
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!(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
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printk(KERN_CONT "enabling native capacity\n");
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bdops->unlock_native_capacity(disk);
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disk->flags |= GENHD_FL_NATIVE_CAPACITY;
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return true;
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} else {
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printk(KERN_CONT "truncated\n");
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return false;
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}
|
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}
|
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|
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static int drop_partitions(struct gendisk *disk, struct block_device *bdev)
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{
|
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struct disk_part_iter piter;
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struct hd_struct *part;
|
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int res;
|
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|
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if (bdev->bd_part_count || bdev->bd_super)
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return -EBUSY;
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res = invalidate_partition(disk, 0);
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if (res)
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return res;
|
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|
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disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
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while ((part = disk_part_iter_next(&piter)))
|
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delete_partition(disk, part->partno);
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disk_part_iter_exit(&piter);
|
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|
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return 0;
|
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}
|
|
|
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static bool part_zone_aligned(struct gendisk *disk,
|
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struct block_device *bdev,
|
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sector_t from, sector_t size)
|
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{
|
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unsigned int zone_sectors = bdev_zone_sectors(bdev);
|
|
|
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/*
|
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* If this function is called, then the disk is a zoned block device
|
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* (host-aware or host-managed). This can be detected even if the
|
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* zoned block device support is disabled (CONFIG_BLK_DEV_ZONED not
|
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* set). In this case, however, only host-aware devices will be seen
|
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* as a block device is not created for host-managed devices. Without
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* zoned block device support, host-aware drives can still be used as
|
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* regular block devices (no zone operation) and their zone size will
|
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* be reported as 0. Allow this case.
|
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*/
|
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if (!zone_sectors)
|
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return true;
|
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|
|
/*
|
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* Check partition start and size alignement. If the drive has a
|
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* smaller last runt zone, ignore it and allow the partition to
|
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* use it. Check the zone size too: it should be a power of 2 number
|
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* of sectors.
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*/
|
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if (WARN_ON_ONCE(!is_power_of_2(zone_sectors))) {
|
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u32 rem;
|
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|
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div_u64_rem(from, zone_sectors, &rem);
|
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if (rem)
|
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return false;
|
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if ((from + size) < get_capacity(disk)) {
|
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div_u64_rem(size, zone_sectors, &rem);
|
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if (rem)
|
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return false;
|
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}
|
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|
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} else {
|
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|
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if (from & (zone_sectors - 1))
|
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return false;
|
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if ((from + size) < get_capacity(disk) &&
|
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(size & (zone_sectors - 1)))
|
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return false;
|
|
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
|
|
{
|
|
struct parsed_partitions *state = NULL;
|
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struct hd_struct *part;
|
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int p, highest, res;
|
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rescan:
|
|
if (state && !IS_ERR(state)) {
|
|
free_partitions(state);
|
|
state = NULL;
|
|
}
|
|
|
|
res = drop_partitions(disk, bdev);
|
|
if (res)
|
|
return res;
|
|
|
|
if (disk->fops->revalidate_disk)
|
|
disk->fops->revalidate_disk(disk);
|
|
check_disk_size_change(disk, bdev);
|
|
bdev->bd_invalidated = 0;
|
|
if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
|
|
return 0;
|
|
if (IS_ERR(state)) {
|
|
/*
|
|
* I/O error reading the partition table. If any
|
|
* partition code tried to read beyond EOD, retry
|
|
* after unlocking native capacity.
|
|
*/
|
|
if (PTR_ERR(state) == -ENOSPC) {
|
|
printk(KERN_WARNING "%s: partition table beyond EOD, ",
|
|
disk->disk_name);
|
|
if (disk_unlock_native_capacity(disk))
|
|
goto rescan;
|
|
}
|
|
return -EIO;
|
|
}
|
|
/*
|
|
* If any partition code tried to read beyond EOD, try
|
|
* unlocking native capacity even if partition table is
|
|
* successfully read as we could be missing some partitions.
|
|
*/
|
|
if (state->access_beyond_eod) {
|
|
printk(KERN_WARNING
|
|
"%s: partition table partially beyond EOD, ",
|
|
disk->disk_name);
|
|
if (disk_unlock_native_capacity(disk))
|
|
goto rescan;
|
|
}
|
|
|
|
/* tell userspace that the media / partition table may have changed */
|
|
kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
|
|
|
|
/* Detect the highest partition number and preallocate
|
|
* disk->part_tbl. This is an optimization and not strictly
|
|
* necessary.
|
|
*/
|
|
for (p = 1, highest = 0; p < state->limit; p++)
|
|
if (state->parts[p].size)
|
|
highest = p;
|
|
|
|
disk_expand_part_tbl(disk, highest);
|
|
|
|
/* add partitions */
|
|
for (p = 1; p < state->limit; p++) {
|
|
sector_t size, from;
|
|
|
|
size = state->parts[p].size;
|
|
if (!size)
|
|
continue;
|
|
|
|
from = state->parts[p].from;
|
|
if (from >= get_capacity(disk)) {
|
|
printk(KERN_WARNING
|
|
"%s: p%d start %llu is beyond EOD, ",
|
|
disk->disk_name, p, (unsigned long long) from);
|
|
if (disk_unlock_native_capacity(disk))
|
|
goto rescan;
|
|
continue;
|
|
}
|
|
|
|
if (from + size > get_capacity(disk)) {
|
|
printk(KERN_WARNING
|
|
"%s: p%d size %llu extends beyond EOD, ",
|
|
disk->disk_name, p, (unsigned long long) size);
|
|
|
|
if (disk_unlock_native_capacity(disk)) {
|
|
/* free state and restart */
|
|
goto rescan;
|
|
} else {
|
|
/*
|
|
* we can not ignore partitions of broken tables
|
|
* created by for example camera firmware, but
|
|
* we limit them to the end of the disk to avoid
|
|
* creating invalid block devices
|
|
*/
|
|
size = get_capacity(disk) - from;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* On a zoned block device, partitions should be aligned on the
|
|
* device zone size (i.e. zone boundary crossing not allowed).
|
|
* Otherwise, resetting the write pointer of the last zone of
|
|
* one partition may impact the following partition.
|
|
*/
|
|
if (bdev_is_zoned(bdev) &&
|
|
!part_zone_aligned(disk, bdev, from, size)) {
|
|
printk(KERN_WARNING
|
|
"%s: p%d start %llu+%llu is not zone aligned\n",
|
|
disk->disk_name, p, (unsigned long long) from,
|
|
(unsigned long long) size);
|
|
continue;
|
|
}
|
|
|
|
part = add_partition(disk, p, from, size,
|
|
state->parts[p].flags,
|
|
&state->parts[p].info);
|
|
if (IS_ERR(part)) {
|
|
printk(KERN_ERR " %s: p%d could not be added: %ld\n",
|
|
disk->disk_name, p, -PTR_ERR(part));
|
|
continue;
|
|
}
|
|
#ifdef CONFIG_BLK_DEV_MD
|
|
if (state->parts[p].flags & ADDPART_FLAG_RAID)
|
|
md_autodetect_dev(part_to_dev(part)->devt);
|
|
#endif
|
|
}
|
|
free_partitions(state);
|
|
return 0;
|
|
}
|
|
|
|
int invalidate_partitions(struct gendisk *disk, struct block_device *bdev)
|
|
{
|
|
int res;
|
|
|
|
if (!bdev->bd_invalidated)
|
|
return 0;
|
|
|
|
res = drop_partitions(disk, bdev);
|
|
if (res)
|
|
return res;
|
|
|
|
set_capacity(disk, 0);
|
|
check_disk_size_change(disk, bdev);
|
|
bdev->bd_invalidated = 0;
|
|
/* tell userspace that the media / partition table may have changed */
|
|
kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
|
|
|
|
return 0;
|
|
}
|
|
|
|
unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
|
|
{
|
|
struct address_space *mapping = bdev->bd_inode->i_mapping;
|
|
struct page *page;
|
|
|
|
page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_SHIFT-9)), NULL);
|
|
if (!IS_ERR(page)) {
|
|
if (PageError(page))
|
|
goto fail;
|
|
p->v = page;
|
|
return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_SHIFT - 9)) - 1)) << 9);
|
|
fail:
|
|
put_page(page);
|
|
}
|
|
p->v = NULL;
|
|
return NULL;
|
|
}
|
|
|
|
EXPORT_SYMBOL(read_dev_sector);
|