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740 lines
17 KiB
740 lines
17 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* Copyright (C) 1991-1998 Linus Torvalds |
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* Re-organised Feb 1998 Russell King |
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* Copyright (C) 2020 Christoph Hellwig |
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*/ |
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#include <linux/fs.h> |
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#include <linux/slab.h> |
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#include <linux/ctype.h> |
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#include <linux/genhd.h> |
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#include <linux/vmalloc.h> |
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#include <linux/blktrace_api.h> |
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#include <linux/raid/detect.h> |
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#include "check.h" |
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|
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static int (*check_part[])(struct parsed_partitions *) = { |
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/* |
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* Probe partition formats with tables at disk address 0 |
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* that also have an ADFS boot block at 0xdc0. |
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*/ |
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#ifdef CONFIG_ACORN_PARTITION_ICS |
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adfspart_check_ICS, |
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#endif |
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#ifdef CONFIG_ACORN_PARTITION_POWERTEC |
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adfspart_check_POWERTEC, |
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#endif |
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#ifdef CONFIG_ACORN_PARTITION_EESOX |
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adfspart_check_EESOX, |
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#endif |
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|
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/* |
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* Now move on to formats that only have partition info at |
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* disk address 0xdc0. Since these may also have stale |
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* PC/BIOS partition tables, they need to come before |
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* the msdos entry. |
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*/ |
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#ifdef CONFIG_ACORN_PARTITION_CUMANA |
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adfspart_check_CUMANA, |
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#endif |
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#ifdef CONFIG_ACORN_PARTITION_ADFS |
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adfspart_check_ADFS, |
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#endif |
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|
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#ifdef CONFIG_CMDLINE_PARTITION |
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cmdline_partition, |
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#endif |
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#ifdef CONFIG_EFI_PARTITION |
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efi_partition, /* this must come before msdos */ |
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#endif |
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#ifdef CONFIG_SGI_PARTITION |
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sgi_partition, |
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#endif |
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#ifdef CONFIG_LDM_PARTITION |
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ldm_partition, /* this must come before msdos */ |
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#endif |
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#ifdef CONFIG_MSDOS_PARTITION |
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msdos_partition, |
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#endif |
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#ifdef CONFIG_OSF_PARTITION |
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osf_partition, |
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#endif |
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#ifdef CONFIG_SUN_PARTITION |
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sun_partition, |
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#endif |
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#ifdef CONFIG_AMIGA_PARTITION |
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amiga_partition, |
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#endif |
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#ifdef CONFIG_ATARI_PARTITION |
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atari_partition, |
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#endif |
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#ifdef CONFIG_MAC_PARTITION |
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mac_partition, |
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#endif |
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#ifdef CONFIG_ULTRIX_PARTITION |
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ultrix_partition, |
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#endif |
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#ifdef CONFIG_IBM_PARTITION |
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ibm_partition, |
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#endif |
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#ifdef CONFIG_KARMA_PARTITION |
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karma_partition, |
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#endif |
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#ifdef CONFIG_SYSV68_PARTITION |
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sysv68_partition, |
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#endif |
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NULL |
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}; |
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|
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static void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors) |
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{ |
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spin_lock(&bdev->bd_size_lock); |
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i_size_write(bdev->bd_inode, (loff_t)sectors << SECTOR_SHIFT); |
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spin_unlock(&bdev->bd_size_lock); |
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} |
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static struct parsed_partitions *allocate_partitions(struct gendisk *hd) |
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{ |
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struct parsed_partitions *state; |
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int nr; |
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state = kzalloc(sizeof(*state), GFP_KERNEL); |
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if (!state) |
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return NULL; |
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nr = disk_max_parts(hd); |
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state->parts = vzalloc(array_size(nr, sizeof(state->parts[0]))); |
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if (!state->parts) { |
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kfree(state); |
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return NULL; |
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} |
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state->limit = nr; |
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return state; |
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} |
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static void free_partitions(struct parsed_partitions *state) |
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{ |
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vfree(state->parts); |
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kfree(state); |
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} |
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static struct parsed_partitions *check_partition(struct gendisk *hd) |
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{ |
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struct parsed_partitions *state; |
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int i, res, err; |
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state = allocate_partitions(hd); |
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if (!state) |
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return NULL; |
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state->pp_buf = (char *)__get_free_page(GFP_KERNEL); |
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if (!state->pp_buf) { |
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free_partitions(state); |
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return NULL; |
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} |
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state->pp_buf[0] = '\0'; |
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state->disk = hd; |
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snprintf(state->name, BDEVNAME_SIZE, "%s", hd->disk_name); |
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snprintf(state->pp_buf, PAGE_SIZE, " %s:", state->name); |
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if (isdigit(state->name[strlen(state->name)-1])) |
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sprintf(state->name, "p"); |
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i = res = err = 0; |
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while (!res && check_part[i]) { |
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memset(state->parts, 0, state->limit * sizeof(state->parts[0])); |
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res = check_part[i++](state); |
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if (res < 0) { |
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/* |
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* We have hit an I/O error which we don't report now. |
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* But record it, and let the others do their job. |
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*/ |
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err = res; |
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res = 0; |
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} |
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} |
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if (res > 0) { |
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printk(KERN_INFO "%s", state->pp_buf); |
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free_page((unsigned long)state->pp_buf); |
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return state; |
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} |
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if (state->access_beyond_eod) |
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err = -ENOSPC; |
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/* |
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* The partition is unrecognized. So report I/O errors if there were any |
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*/ |
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if (err) |
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res = err; |
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if (res) { |
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strlcat(state->pp_buf, |
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" unable to read partition table\n", PAGE_SIZE); |
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printk(KERN_INFO "%s", state->pp_buf); |
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} |
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free_page((unsigned long)state->pp_buf); |
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free_partitions(state); |
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return ERR_PTR(res); |
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} |
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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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return sprintf(buf, "%d\n", dev_to_bdev(dev)->bd_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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return sprintf(buf, "%llu\n", dev_to_bdev(dev)->bd_start_sect); |
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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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return sprintf(buf, "%d\n", bdev_read_only(dev_to_bdev(dev))); |
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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 block_device *bdev = dev_to_bdev(dev); |
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return sprintf(buf, "%u\n", |
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queue_limit_alignment_offset(&bdev->bd_disk->queue->limits, |
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bdev->bd_start_sect)); |
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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 block_device *bdev = dev_to_bdev(dev); |
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return sprintf(buf, "%u\n", |
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queue_limit_discard_alignment(&bdev->bd_disk->queue->limits, |
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bdev->bd_start_sect)); |
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} |
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static DEVICE_ATTR(partition, 0444, part_partition_show, NULL); |
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static DEVICE_ATTR(start, 0444, part_start_show, NULL); |
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static DEVICE_ATTR(size, 0444, part_size_show, NULL); |
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static DEVICE_ATTR(ro, 0444, part_ro_show, NULL); |
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static DEVICE_ATTR(alignment_offset, 0444, part_alignment_offset_show, NULL); |
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static DEVICE_ATTR(discard_alignment, 0444, part_discard_alignment_show, NULL); |
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static DEVICE_ATTR(stat, 0444, part_stat_show, NULL); |
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static DEVICE_ATTR(inflight, 0444, 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, 0644, 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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put_disk(dev_to_bdev(dev)->bd_disk); |
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iput(dev_to_bdev(dev)->bd_inode); |
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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 block_device *part = dev_to_bdev(dev); |
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add_uevent_var(env, "PARTN=%u", part->bd_partno); |
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if (part->bd_meta_info && part->bd_meta_info->volname[0]) |
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add_uevent_var(env, "PARTNAME=%s", part->bd_meta_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(struct block_device *part) |
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{ |
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lockdep_assert_held(&part->bd_disk->open_mutex); |
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fsync_bdev(part); |
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__invalidate_device(part, true); |
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xa_erase(&part->bd_disk->part_tbl, part->bd_partno); |
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kobject_put(part->bd_holder_dir); |
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device_del(&part->bd_device); |
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/* |
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* Remove the block device from the inode hash, so that it cannot be |
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* looked up any more even when openers still hold references. |
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*/ |
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remove_inode_hash(part->bd_inode); |
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put_device(&part->bd_device); |
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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, 0444, whole_disk_show, NULL); |
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/* |
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* Must be called either with open_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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static struct block_device *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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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 block_device *bdev; |
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const char *dname; |
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int err; |
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lockdep_assert_held(&disk->open_mutex); |
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if (partno >= disk_max_parts(disk)) |
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return ERR_PTR(-EINVAL); |
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/* |
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* Partitions are not supported on zoned block devices that are used as |
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* such. |
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*/ |
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switch (disk->queue->limits.zoned) { |
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case BLK_ZONED_HM: |
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pr_warn("%s: partitions not supported on host managed zoned block device\n", |
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disk->disk_name); |
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return ERR_PTR(-ENXIO); |
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case BLK_ZONED_HA: |
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pr_info("%s: disabling host aware zoned block device support due to partitions\n", |
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disk->disk_name); |
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blk_queue_set_zoned(disk, BLK_ZONED_NONE); |
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break; |
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case BLK_ZONED_NONE: |
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break; |
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} |
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if (xa_load(&disk->part_tbl, partno)) |
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return ERR_PTR(-EBUSY); |
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/* ensure we always have a reference to the whole disk */ |
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get_device(disk_to_dev(disk)); |
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err = -ENOMEM; |
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bdev = bdev_alloc(disk, partno); |
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if (!bdev) |
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goto out_put_disk; |
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bdev->bd_start_sect = start; |
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bdev_set_nr_sectors(bdev, len); |
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pdev = &bdev->bd_device; |
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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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/* in consecutive minor range? */ |
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if (bdev->bd_partno < disk->minors) { |
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devt = MKDEV(disk->major, disk->first_minor + bdev->bd_partno); |
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} else { |
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err = blk_alloc_ext_minor(); |
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if (err < 0) |
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goto out_put; |
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devt = MKDEV(BLOCK_EXT_MAJOR, err); |
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} |
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pdev->devt = devt; |
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if (info) { |
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err = -ENOMEM; |
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bdev->bd_meta_info = kmemdup(info, sizeof(*info), GFP_KERNEL); |
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if (!bdev->bd_meta_info) |
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goto out_put; |
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} |
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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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bdev->bd_holder_dir = kobject_create_and_add("holders", &pdev->kobj); |
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if (!bdev->bd_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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/* everything is up and running, commence */ |
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err = xa_insert(&disk->part_tbl, partno, bdev, GFP_KERNEL); |
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if (err) |
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goto out_del; |
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bdev_add(bdev, devt); |
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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 bdev; |
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out_del: |
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kobject_put(bdev->bd_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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out_put_disk: |
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put_disk(disk); |
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return ERR_PTR(err); |
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} |
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static bool partition_overlaps(struct gendisk *disk, sector_t start, |
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sector_t length, int skip_partno) |
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{ |
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struct block_device *part; |
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bool overlap = false; |
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unsigned long idx; |
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rcu_read_lock(); |
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xa_for_each_start(&disk->part_tbl, idx, part, 1) { |
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if (part->bd_partno != skip_partno && |
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start < part->bd_start_sect + bdev_nr_sectors(part) && |
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start + length > part->bd_start_sect) { |
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overlap = true; |
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break; |
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} |
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} |
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rcu_read_unlock(); |
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return overlap; |
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} |
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int bdev_add_partition(struct gendisk *disk, int partno, sector_t start, |
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sector_t length) |
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{ |
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struct block_device *part; |
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int ret; |
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mutex_lock(&disk->open_mutex); |
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if (!disk_live(disk)) { |
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ret = -ENXIO; |
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goto out; |
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} |
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if (partition_overlaps(disk, start, length, -1)) { |
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ret = -EBUSY; |
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goto out; |
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} |
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part = add_partition(disk, partno, start, length, |
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ADDPART_FLAG_NONE, NULL); |
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ret = PTR_ERR_OR_ZERO(part); |
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out: |
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mutex_unlock(&disk->open_mutex); |
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return ret; |
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} |
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int bdev_del_partition(struct gendisk *disk, int partno) |
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{ |
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struct block_device *part = NULL; |
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int ret = -ENXIO; |
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mutex_lock(&disk->open_mutex); |
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part = xa_load(&disk->part_tbl, partno); |
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if (!part) |
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goto out_unlock; |
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ret = -EBUSY; |
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if (part->bd_openers) |
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goto out_unlock; |
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delete_partition(part); |
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ret = 0; |
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out_unlock: |
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mutex_unlock(&disk->open_mutex); |
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return ret; |
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} |
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int bdev_resize_partition(struct gendisk *disk, int partno, sector_t start, |
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sector_t length) |
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{ |
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struct block_device *part = NULL; |
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int ret = -ENXIO; |
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mutex_lock(&disk->open_mutex); |
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part = xa_load(&disk->part_tbl, partno); |
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if (!part) |
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goto out_unlock; |
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ret = -EINVAL; |
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if (start != part->bd_start_sect) |
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goto out_unlock; |
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ret = -EBUSY; |
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if (partition_overlaps(disk, start, length, partno)) |
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goto out_unlock; |
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bdev_set_nr_sectors(part, length); |
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ret = 0; |
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out_unlock: |
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mutex_unlock(&disk->open_mutex); |
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return ret; |
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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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void blk_drop_partitions(struct gendisk *disk) |
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{ |
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struct block_device *part; |
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unsigned long idx; |
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|
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lockdep_assert_held(&disk->open_mutex); |
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|
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xa_for_each_start(&disk->part_tbl, idx, part, 1) |
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delete_partition(part); |
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} |
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|
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static bool blk_add_partition(struct gendisk *disk, |
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struct parsed_partitions *state, int p) |
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{ |
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sector_t size = state->parts[p].size; |
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sector_t from = state->parts[p].from; |
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struct block_device *part; |
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if (!size) |
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return true; |
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if (from >= get_capacity(disk)) { |
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printk(KERN_WARNING |
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"%s: p%d start %llu is beyond EOD, ", |
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disk->disk_name, p, (unsigned long long) from); |
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if (disk_unlock_native_capacity(disk)) |
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return false; |
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return true; |
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} |
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|
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if (from + size > get_capacity(disk)) { |
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printk(KERN_WARNING |
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"%s: p%d size %llu extends beyond EOD, ", |
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disk->disk_name, p, (unsigned long long) size); |
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|
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if (disk_unlock_native_capacity(disk)) |
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return false; |
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|
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/* |
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* We can not ignore partitions of broken tables created by for |
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* example camera firmware, but we limit them to the end of the |
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* disk to avoid creating invalid block devices. |
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*/ |
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size = get_capacity(disk) - from; |
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} |
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part = add_partition(disk, p, from, size, state->parts[p].flags, |
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&state->parts[p].info); |
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if (IS_ERR(part) && PTR_ERR(part) != -ENXIO) { |
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printk(KERN_ERR " %s: p%d could not be added: %ld\n", |
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disk->disk_name, p, -PTR_ERR(part)); |
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return true; |
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} |
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|
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if (IS_BUILTIN(CONFIG_BLK_DEV_MD) && |
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(state->parts[p].flags & ADDPART_FLAG_RAID)) |
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md_autodetect_dev(part->bd_dev); |
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|
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return true; |
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} |
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|
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static int blk_add_partitions(struct gendisk *disk) |
|
{ |
|
struct parsed_partitions *state; |
|
int ret = -EAGAIN, p; |
|
|
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if (!disk_part_scan_enabled(disk)) |
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return 0; |
|
|
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state = check_partition(disk); |
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if (!state) |
|
return 0; |
|
if (IS_ERR(state)) { |
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/* |
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* I/O error reading the partition table. If we tried to read |
|
* beyond EOD, retry after unlocking the native capacity. |
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*/ |
|
if (PTR_ERR(state) == -ENOSPC) { |
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printk(KERN_WARNING "%s: partition table beyond EOD, ", |
|
disk->disk_name); |
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if (disk_unlock_native_capacity(disk)) |
|
return -EAGAIN; |
|
} |
|
return -EIO; |
|
} |
|
|
|
/* |
|
* Partitions are not supported on host managed zoned block devices. |
|
*/ |
|
if (disk->queue->limits.zoned == BLK_ZONED_HM) { |
|
pr_warn("%s: ignoring partition table on host managed zoned block device\n", |
|
disk->disk_name); |
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ret = 0; |
|
goto out_free_state; |
|
} |
|
|
|
/* |
|
* If we read beyond EOD, try unlocking native capacity even if the |
|
* partition table was 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 out_free_state; |
|
} |
|
|
|
/* tell userspace that the media / partition table may have changed */ |
|
kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); |
|
|
|
for (p = 1; p < state->limit; p++) |
|
if (!blk_add_partition(disk, state, p)) |
|
goto out_free_state; |
|
|
|
ret = 0; |
|
out_free_state: |
|
free_partitions(state); |
|
return ret; |
|
} |
|
|
|
int bdev_disk_changed(struct gendisk *disk, bool invalidate) |
|
{ |
|
int ret = 0; |
|
|
|
lockdep_assert_held(&disk->open_mutex); |
|
|
|
if (!disk_live(disk)) |
|
return -ENXIO; |
|
|
|
rescan: |
|
if (disk->open_partitions) |
|
return -EBUSY; |
|
sync_blockdev(disk->part0); |
|
invalidate_bdev(disk->part0); |
|
blk_drop_partitions(disk); |
|
|
|
clear_bit(GD_NEED_PART_SCAN, &disk->state); |
|
|
|
/* |
|
* Historically we only set the capacity to zero for devices that |
|
* support partitions (independ of actually having partitions created). |
|
* Doing that is rather inconsistent, but changing it broke legacy |
|
* udisks polling for legacy ide-cdrom devices. Use the crude check |
|
* below to get the sane behavior for most device while not breaking |
|
* userspace for this particular setup. |
|
*/ |
|
if (invalidate) { |
|
if (disk_part_scan_enabled(disk) || |
|
!(disk->flags & GENHD_FL_REMOVABLE)) |
|
set_capacity(disk, 0); |
|
} |
|
|
|
if (get_capacity(disk)) { |
|
ret = blk_add_partitions(disk); |
|
if (ret == -EAGAIN) |
|
goto rescan; |
|
} else if (invalidate) { |
|
/* |
|
* Tell userspace that the media / partition table may have |
|
* changed. |
|
*/ |
|
kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); |
|
} |
|
|
|
return ret; |
|
} |
|
/* |
|
* Only exported for loop and dasd for historic reasons. Don't use in new |
|
* code! |
|
*/ |
|
EXPORT_SYMBOL_GPL(bdev_disk_changed); |
|
|
|
void *read_part_sector(struct parsed_partitions *state, sector_t n, Sector *p) |
|
{ |
|
struct address_space *mapping = state->disk->part0->bd_inode->i_mapping; |
|
struct page *page; |
|
|
|
if (n >= get_capacity(state->disk)) { |
|
state->access_beyond_eod = true; |
|
return NULL; |
|
} |
|
|
|
page = read_mapping_page(mapping, |
|
(pgoff_t)(n >> (PAGE_SHIFT - 9)), NULL); |
|
if (IS_ERR(page)) |
|
goto out; |
|
if (PageError(page)) |
|
goto out_put_page; |
|
|
|
p->v = page; |
|
return (unsigned char *)page_address(page) + |
|
((n & ((1 << (PAGE_SHIFT - 9)) - 1)) << SECTOR_SHIFT); |
|
out_put_page: |
|
put_page(page); |
|
out: |
|
p->v = NULL; |
|
return NULL; |
|
}
|
|
|