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![Linus Torvalds](/assets/img/avatar_default.png)
Here is the big set of char / misc and other driver subsystem updates for 5.14-rc1. Included in here are: - habanna driver updates - fsl-mc driver updates - comedi driver updates - fpga driver updates - extcon driver updates - interconnect driver updates - mei driver updates - nvmem driver updates - phy driver updates - pnp driver updates - soundwire driver updates - lots of other tiny driver updates for char and misc drivers This is looking more and more like the "various driver subsystems mushed together" tree... All of these have been in linux-next for a while with no reported issues. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> -----BEGIN PGP SIGNATURE----- iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCYOM8jQ8cZ3JlZ0Brcm9h aC5jb20ACgkQMUfUDdst+ymECgCg0yL+8WxDKO5Gg5llM5PshvLB1rQAn0y5pDgg nw78LV3HQ0U7qaZBtI91 =x+AR -----END PGP SIGNATURE----- Merge tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char / misc driver updates from Greg KH: "Here is the big set of char / misc and other driver subsystem updates for 5.14-rc1. Included in here are: - habanalabs driver updates - fsl-mc driver updates - comedi driver updates - fpga driver updates - extcon driver updates - interconnect driver updates - mei driver updates - nvmem driver updates - phy driver updates - pnp driver updates - soundwire driver updates - lots of other tiny driver updates for char and misc drivers This is looking more and more like the "various driver subsystems mushed together" tree... All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits) mcb: Use DEFINE_RES_MEM() helper macro and fix the end address PNP: moved EXPORT_SYMBOL so that it immediately followed its function/variable bus: mhi: pci-generic: Add missing 'pci_disable_pcie_error_reporting()' calls bus: mhi: Wait for M2 state during system resume bus: mhi: core: Fix power down latency intel_th: Wait until port is in reset before programming it intel_th: msu: Make contiguous buffers uncached intel_th: Remove an unused exit point from intel_th_remove() stm class: Spelling fix nitro_enclaves: Set Bus Master for the NE PCI device misc: ibmasm: Modify matricies to matrices misc: vmw_vmci: return the correct errno code siox: Simplify error handling via dev_err_probe() fpga: machxo2-spi: Address warning about unused variable lkdtm/heap: Add init_on_alloc tests selftests/lkdtm: Enable various testable CONFIGs lkdtm: Add CONFIG hints in errors where possible lkdtm: Enable DOUBLE_FAULT on all architectures lkdtm/heap: Add vmalloc linear overflow test lkdtm/bugs: XFAIL UNALIGNED_LOAD_STORE_WRITE ...
1876 lines
46 KiB
C
1876 lines
46 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (C) 1991, 1992 Linus Torvalds
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* Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
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* Copyright (C) 2016 - 2020 Christoph Hellwig
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*/
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/fcntl.h>
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#include <linux/slab.h>
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#include <linux/kmod.h>
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#include <linux/major.h>
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#include <linux/device_cgroup.h>
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#include <linux/highmem.h>
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#include <linux/blkdev.h>
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#include <linux/backing-dev.h>
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#include <linux/module.h>
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#include <linux/blkpg.h>
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#include <linux/magic.h>
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#include <linux/buffer_head.h>
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#include <linux/swap.h>
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#include <linux/pagevec.h>
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#include <linux/writeback.h>
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#include <linux/mpage.h>
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#include <linux/mount.h>
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#include <linux/pseudo_fs.h>
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#include <linux/uio.h>
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#include <linux/namei.h>
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#include <linux/log2.h>
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#include <linux/cleancache.h>
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#include <linux/task_io_accounting_ops.h>
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#include <linux/falloc.h>
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#include <linux/part_stat.h>
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#include <linux/uaccess.h>
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#include <linux/suspend.h>
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#include "internal.h"
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struct bdev_inode {
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struct block_device bdev;
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struct inode vfs_inode;
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};
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static const struct address_space_operations def_blk_aops;
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static inline struct bdev_inode *BDEV_I(struct inode *inode)
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{
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return container_of(inode, struct bdev_inode, vfs_inode);
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}
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struct block_device *I_BDEV(struct inode *inode)
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{
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return &BDEV_I(inode)->bdev;
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}
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EXPORT_SYMBOL(I_BDEV);
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static void bdev_write_inode(struct block_device *bdev)
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{
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struct inode *inode = bdev->bd_inode;
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int ret;
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spin_lock(&inode->i_lock);
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while (inode->i_state & I_DIRTY) {
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spin_unlock(&inode->i_lock);
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ret = write_inode_now(inode, true);
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if (ret) {
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char name[BDEVNAME_SIZE];
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pr_warn_ratelimited("VFS: Dirty inode writeback failed "
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"for block device %s (err=%d).\n",
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bdevname(bdev, name), ret);
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}
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spin_lock(&inode->i_lock);
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}
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spin_unlock(&inode->i_lock);
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}
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/* Kill _all_ buffers and pagecache , dirty or not.. */
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static void kill_bdev(struct block_device *bdev)
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{
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struct address_space *mapping = bdev->bd_inode->i_mapping;
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if (mapping_empty(mapping))
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return;
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invalidate_bh_lrus();
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truncate_inode_pages(mapping, 0);
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}
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/* Invalidate clean unused buffers and pagecache. */
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void invalidate_bdev(struct block_device *bdev)
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{
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struct address_space *mapping = bdev->bd_inode->i_mapping;
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if (mapping->nrpages) {
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invalidate_bh_lrus();
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lru_add_drain_all(); /* make sure all lru add caches are flushed */
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invalidate_mapping_pages(mapping, 0, -1);
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}
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/* 99% of the time, we don't need to flush the cleancache on the bdev.
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* But, for the strange corners, lets be cautious
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*/
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cleancache_invalidate_inode(mapping);
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}
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EXPORT_SYMBOL(invalidate_bdev);
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/*
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* Drop all buffers & page cache for given bdev range. This function bails
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* with error if bdev has other exclusive owner (such as filesystem).
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*/
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int truncate_bdev_range(struct block_device *bdev, fmode_t mode,
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loff_t lstart, loff_t lend)
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{
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/*
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* If we don't hold exclusive handle for the device, upgrade to it
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* while we discard the buffer cache to avoid discarding buffers
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* under live filesystem.
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*/
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if (!(mode & FMODE_EXCL)) {
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int err = bd_prepare_to_claim(bdev, truncate_bdev_range);
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if (err)
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goto invalidate;
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}
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truncate_inode_pages_range(bdev->bd_inode->i_mapping, lstart, lend);
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if (!(mode & FMODE_EXCL))
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bd_abort_claiming(bdev, truncate_bdev_range);
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return 0;
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invalidate:
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/*
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* Someone else has handle exclusively open. Try invalidating instead.
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* The 'end' argument is inclusive so the rounding is safe.
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*/
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return invalidate_inode_pages2_range(bdev->bd_inode->i_mapping,
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lstart >> PAGE_SHIFT,
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lend >> PAGE_SHIFT);
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}
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static void set_init_blocksize(struct block_device *bdev)
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{
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unsigned int bsize = bdev_logical_block_size(bdev);
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loff_t size = i_size_read(bdev->bd_inode);
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while (bsize < PAGE_SIZE) {
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if (size & bsize)
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break;
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bsize <<= 1;
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}
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bdev->bd_inode->i_blkbits = blksize_bits(bsize);
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}
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int set_blocksize(struct block_device *bdev, int size)
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{
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/* Size must be a power of two, and between 512 and PAGE_SIZE */
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if (size > PAGE_SIZE || size < 512 || !is_power_of_2(size))
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return -EINVAL;
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/* Size cannot be smaller than the size supported by the device */
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if (size < bdev_logical_block_size(bdev))
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return -EINVAL;
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/* Don't change the size if it is same as current */
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if (bdev->bd_inode->i_blkbits != blksize_bits(size)) {
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sync_blockdev(bdev);
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bdev->bd_inode->i_blkbits = blksize_bits(size);
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kill_bdev(bdev);
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}
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return 0;
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}
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EXPORT_SYMBOL(set_blocksize);
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int sb_set_blocksize(struct super_block *sb, int size)
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{
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if (set_blocksize(sb->s_bdev, size))
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return 0;
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/* If we get here, we know size is power of two
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* and it's value is between 512 and PAGE_SIZE */
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sb->s_blocksize = size;
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sb->s_blocksize_bits = blksize_bits(size);
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return sb->s_blocksize;
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}
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EXPORT_SYMBOL(sb_set_blocksize);
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int sb_min_blocksize(struct super_block *sb, int size)
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{
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int minsize = bdev_logical_block_size(sb->s_bdev);
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if (size < minsize)
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size = minsize;
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return sb_set_blocksize(sb, size);
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}
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EXPORT_SYMBOL(sb_min_blocksize);
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static int
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blkdev_get_block(struct inode *inode, sector_t iblock,
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struct buffer_head *bh, int create)
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{
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bh->b_bdev = I_BDEV(inode);
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bh->b_blocknr = iblock;
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set_buffer_mapped(bh);
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return 0;
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}
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static struct inode *bdev_file_inode(struct file *file)
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{
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return file->f_mapping->host;
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}
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static unsigned int dio_bio_write_op(struct kiocb *iocb)
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{
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unsigned int op = REQ_OP_WRITE | REQ_SYNC | REQ_IDLE;
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/* avoid the need for a I/O completion work item */
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if (iocb->ki_flags & IOCB_DSYNC)
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op |= REQ_FUA;
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return op;
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}
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#define DIO_INLINE_BIO_VECS 4
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static void blkdev_bio_end_io_simple(struct bio *bio)
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{
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struct task_struct *waiter = bio->bi_private;
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WRITE_ONCE(bio->bi_private, NULL);
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blk_wake_io_task(waiter);
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}
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static ssize_t
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__blkdev_direct_IO_simple(struct kiocb *iocb, struct iov_iter *iter,
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unsigned int nr_pages)
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{
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struct file *file = iocb->ki_filp;
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struct block_device *bdev = I_BDEV(bdev_file_inode(file));
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struct bio_vec inline_vecs[DIO_INLINE_BIO_VECS], *vecs;
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loff_t pos = iocb->ki_pos;
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bool should_dirty = false;
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struct bio bio;
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ssize_t ret;
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blk_qc_t qc;
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if ((pos | iov_iter_alignment(iter)) &
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(bdev_logical_block_size(bdev) - 1))
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return -EINVAL;
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if (nr_pages <= DIO_INLINE_BIO_VECS)
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vecs = inline_vecs;
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else {
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vecs = kmalloc_array(nr_pages, sizeof(struct bio_vec),
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GFP_KERNEL);
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if (!vecs)
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return -ENOMEM;
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}
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bio_init(&bio, vecs, nr_pages);
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bio_set_dev(&bio, bdev);
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bio.bi_iter.bi_sector = pos >> 9;
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bio.bi_write_hint = iocb->ki_hint;
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bio.bi_private = current;
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bio.bi_end_io = blkdev_bio_end_io_simple;
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bio.bi_ioprio = iocb->ki_ioprio;
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ret = bio_iov_iter_get_pages(&bio, iter);
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if (unlikely(ret))
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goto out;
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ret = bio.bi_iter.bi_size;
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if (iov_iter_rw(iter) == READ) {
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bio.bi_opf = REQ_OP_READ;
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if (iter_is_iovec(iter))
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should_dirty = true;
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} else {
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bio.bi_opf = dio_bio_write_op(iocb);
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task_io_account_write(ret);
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}
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if (iocb->ki_flags & IOCB_NOWAIT)
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bio.bi_opf |= REQ_NOWAIT;
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if (iocb->ki_flags & IOCB_HIPRI)
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bio_set_polled(&bio, iocb);
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qc = submit_bio(&bio);
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for (;;) {
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set_current_state(TASK_UNINTERRUPTIBLE);
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if (!READ_ONCE(bio.bi_private))
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break;
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if (!(iocb->ki_flags & IOCB_HIPRI) ||
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!blk_poll(bdev_get_queue(bdev), qc, true))
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blk_io_schedule();
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}
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__set_current_state(TASK_RUNNING);
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bio_release_pages(&bio, should_dirty);
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if (unlikely(bio.bi_status))
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ret = blk_status_to_errno(bio.bi_status);
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out:
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if (vecs != inline_vecs)
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kfree(vecs);
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bio_uninit(&bio);
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return ret;
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}
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struct blkdev_dio {
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union {
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struct kiocb *iocb;
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struct task_struct *waiter;
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};
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size_t size;
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atomic_t ref;
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bool multi_bio : 1;
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bool should_dirty : 1;
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bool is_sync : 1;
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struct bio bio;
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};
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static struct bio_set blkdev_dio_pool;
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static int blkdev_iopoll(struct kiocb *kiocb, bool wait)
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{
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struct block_device *bdev = I_BDEV(kiocb->ki_filp->f_mapping->host);
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struct request_queue *q = bdev_get_queue(bdev);
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return blk_poll(q, READ_ONCE(kiocb->ki_cookie), wait);
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}
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static void blkdev_bio_end_io(struct bio *bio)
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{
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struct blkdev_dio *dio = bio->bi_private;
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bool should_dirty = dio->should_dirty;
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if (bio->bi_status && !dio->bio.bi_status)
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dio->bio.bi_status = bio->bi_status;
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if (!dio->multi_bio || atomic_dec_and_test(&dio->ref)) {
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if (!dio->is_sync) {
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struct kiocb *iocb = dio->iocb;
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ssize_t ret;
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if (likely(!dio->bio.bi_status)) {
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ret = dio->size;
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iocb->ki_pos += ret;
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} else {
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ret = blk_status_to_errno(dio->bio.bi_status);
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}
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dio->iocb->ki_complete(iocb, ret, 0);
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if (dio->multi_bio)
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bio_put(&dio->bio);
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} else {
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struct task_struct *waiter = dio->waiter;
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WRITE_ONCE(dio->waiter, NULL);
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blk_wake_io_task(waiter);
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}
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}
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if (should_dirty) {
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bio_check_pages_dirty(bio);
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} else {
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bio_release_pages(bio, false);
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bio_put(bio);
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}
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}
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|
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static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
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unsigned int nr_pages)
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{
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struct file *file = iocb->ki_filp;
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struct inode *inode = bdev_file_inode(file);
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struct block_device *bdev = I_BDEV(inode);
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struct blk_plug plug;
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struct blkdev_dio *dio;
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struct bio *bio;
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bool is_poll = (iocb->ki_flags & IOCB_HIPRI) != 0;
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bool is_read = (iov_iter_rw(iter) == READ), is_sync;
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loff_t pos = iocb->ki_pos;
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blk_qc_t qc = BLK_QC_T_NONE;
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int ret = 0;
|
|
|
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if ((pos | iov_iter_alignment(iter)) &
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(bdev_logical_block_size(bdev) - 1))
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return -EINVAL;
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bio = bio_alloc_bioset(GFP_KERNEL, nr_pages, &blkdev_dio_pool);
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dio = container_of(bio, struct blkdev_dio, bio);
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dio->is_sync = is_sync = is_sync_kiocb(iocb);
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if (dio->is_sync) {
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dio->waiter = current;
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bio_get(bio);
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} else {
|
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dio->iocb = iocb;
|
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}
|
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|
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dio->size = 0;
|
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dio->multi_bio = false;
|
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dio->should_dirty = is_read && iter_is_iovec(iter);
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|
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/*
|
|
* Don't plug for HIPRI/polled IO, as those should go straight
|
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* to issue
|
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*/
|
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if (!is_poll)
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blk_start_plug(&plug);
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|
|
|
for (;;) {
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bio_set_dev(bio, bdev);
|
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bio->bi_iter.bi_sector = pos >> 9;
|
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bio->bi_write_hint = iocb->ki_hint;
|
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bio->bi_private = dio;
|
|
bio->bi_end_io = blkdev_bio_end_io;
|
|
bio->bi_ioprio = iocb->ki_ioprio;
|
|
|
|
ret = bio_iov_iter_get_pages(bio, iter);
|
|
if (unlikely(ret)) {
|
|
bio->bi_status = BLK_STS_IOERR;
|
|
bio_endio(bio);
|
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break;
|
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}
|
|
|
|
if (is_read) {
|
|
bio->bi_opf = REQ_OP_READ;
|
|
if (dio->should_dirty)
|
|
bio_set_pages_dirty(bio);
|
|
} else {
|
|
bio->bi_opf = dio_bio_write_op(iocb);
|
|
task_io_account_write(bio->bi_iter.bi_size);
|
|
}
|
|
if (iocb->ki_flags & IOCB_NOWAIT)
|
|
bio->bi_opf |= REQ_NOWAIT;
|
|
|
|
dio->size += bio->bi_iter.bi_size;
|
|
pos += bio->bi_iter.bi_size;
|
|
|
|
nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS);
|
|
if (!nr_pages) {
|
|
bool polled = false;
|
|
|
|
if (iocb->ki_flags & IOCB_HIPRI) {
|
|
bio_set_polled(bio, iocb);
|
|
polled = true;
|
|
}
|
|
|
|
qc = submit_bio(bio);
|
|
|
|
if (polled)
|
|
WRITE_ONCE(iocb->ki_cookie, qc);
|
|
break;
|
|
}
|
|
|
|
if (!dio->multi_bio) {
|
|
/*
|
|
* AIO needs an extra reference to ensure the dio
|
|
* structure which is embedded into the first bio
|
|
* stays around.
|
|
*/
|
|
if (!is_sync)
|
|
bio_get(bio);
|
|
dio->multi_bio = true;
|
|
atomic_set(&dio->ref, 2);
|
|
} else {
|
|
atomic_inc(&dio->ref);
|
|
}
|
|
|
|
submit_bio(bio);
|
|
bio = bio_alloc(GFP_KERNEL, nr_pages);
|
|
}
|
|
|
|
if (!is_poll)
|
|
blk_finish_plug(&plug);
|
|
|
|
if (!is_sync)
|
|
return -EIOCBQUEUED;
|
|
|
|
for (;;) {
|
|
set_current_state(TASK_UNINTERRUPTIBLE);
|
|
if (!READ_ONCE(dio->waiter))
|
|
break;
|
|
|
|
if (!(iocb->ki_flags & IOCB_HIPRI) ||
|
|
!blk_poll(bdev_get_queue(bdev), qc, true))
|
|
blk_io_schedule();
|
|
}
|
|
__set_current_state(TASK_RUNNING);
|
|
|
|
if (!ret)
|
|
ret = blk_status_to_errno(dio->bio.bi_status);
|
|
if (likely(!ret))
|
|
ret = dio->size;
|
|
|
|
bio_put(&dio->bio);
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t
|
|
blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
|
|
{
|
|
unsigned int nr_pages;
|
|
|
|
if (!iov_iter_count(iter))
|
|
return 0;
|
|
|
|
nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS + 1);
|
|
if (is_sync_kiocb(iocb) && nr_pages <= BIO_MAX_VECS)
|
|
return __blkdev_direct_IO_simple(iocb, iter, nr_pages);
|
|
|
|
return __blkdev_direct_IO(iocb, iter, bio_max_segs(nr_pages));
|
|
}
|
|
|
|
static __init int blkdev_init(void)
|
|
{
|
|
return bioset_init(&blkdev_dio_pool, 4, offsetof(struct blkdev_dio, bio), BIOSET_NEED_BVECS);
|
|
}
|
|
module_init(blkdev_init);
|
|
|
|
int __sync_blockdev(struct block_device *bdev, int wait)
|
|
{
|
|
if (!bdev)
|
|
return 0;
|
|
if (!wait)
|
|
return filemap_flush(bdev->bd_inode->i_mapping);
|
|
return filemap_write_and_wait(bdev->bd_inode->i_mapping);
|
|
}
|
|
|
|
/*
|
|
* Write out and wait upon all the dirty data associated with a block
|
|
* device via its mapping. Does not take the superblock lock.
|
|
*/
|
|
int sync_blockdev(struct block_device *bdev)
|
|
{
|
|
return __sync_blockdev(bdev, 1);
|
|
}
|
|
EXPORT_SYMBOL(sync_blockdev);
|
|
|
|
/*
|
|
* Write out and wait upon all dirty data associated with this
|
|
* device. Filesystem data as well as the underlying block
|
|
* device. Takes the superblock lock.
|
|
*/
|
|
int fsync_bdev(struct block_device *bdev)
|
|
{
|
|
struct super_block *sb = get_super(bdev);
|
|
if (sb) {
|
|
int res = sync_filesystem(sb);
|
|
drop_super(sb);
|
|
return res;
|
|
}
|
|
return sync_blockdev(bdev);
|
|
}
|
|
EXPORT_SYMBOL(fsync_bdev);
|
|
|
|
/**
|
|
* freeze_bdev -- lock a filesystem and force it into a consistent state
|
|
* @bdev: blockdevice to lock
|
|
*
|
|
* If a superblock is found on this device, we take the s_umount semaphore
|
|
* on it to make sure nobody unmounts until the snapshot creation is done.
|
|
* The reference counter (bd_fsfreeze_count) guarantees that only the last
|
|
* unfreeze process can unfreeze the frozen filesystem actually when multiple
|
|
* freeze requests arrive simultaneously. It counts up in freeze_bdev() and
|
|
* count down in thaw_bdev(). When it becomes 0, thaw_bdev() will unfreeze
|
|
* actually.
|
|
*/
|
|
int freeze_bdev(struct block_device *bdev)
|
|
{
|
|
struct super_block *sb;
|
|
int error = 0;
|
|
|
|
mutex_lock(&bdev->bd_fsfreeze_mutex);
|
|
if (++bdev->bd_fsfreeze_count > 1)
|
|
goto done;
|
|
|
|
sb = get_active_super(bdev);
|
|
if (!sb)
|
|
goto sync;
|
|
if (sb->s_op->freeze_super)
|
|
error = sb->s_op->freeze_super(sb);
|
|
else
|
|
error = freeze_super(sb);
|
|
deactivate_super(sb);
|
|
|
|
if (error) {
|
|
bdev->bd_fsfreeze_count--;
|
|
goto done;
|
|
}
|
|
bdev->bd_fsfreeze_sb = sb;
|
|
|
|
sync:
|
|
sync_blockdev(bdev);
|
|
done:
|
|
mutex_unlock(&bdev->bd_fsfreeze_mutex);
|
|
return error;
|
|
}
|
|
EXPORT_SYMBOL(freeze_bdev);
|
|
|
|
/**
|
|
* thaw_bdev -- unlock filesystem
|
|
* @bdev: blockdevice to unlock
|
|
*
|
|
* Unlocks the filesystem and marks it writeable again after freeze_bdev().
|
|
*/
|
|
int thaw_bdev(struct block_device *bdev)
|
|
{
|
|
struct super_block *sb;
|
|
int error = -EINVAL;
|
|
|
|
mutex_lock(&bdev->bd_fsfreeze_mutex);
|
|
if (!bdev->bd_fsfreeze_count)
|
|
goto out;
|
|
|
|
error = 0;
|
|
if (--bdev->bd_fsfreeze_count > 0)
|
|
goto out;
|
|
|
|
sb = bdev->bd_fsfreeze_sb;
|
|
if (!sb)
|
|
goto out;
|
|
|
|
if (sb->s_op->thaw_super)
|
|
error = sb->s_op->thaw_super(sb);
|
|
else
|
|
error = thaw_super(sb);
|
|
if (error)
|
|
bdev->bd_fsfreeze_count++;
|
|
else
|
|
bdev->bd_fsfreeze_sb = NULL;
|
|
out:
|
|
mutex_unlock(&bdev->bd_fsfreeze_mutex);
|
|
return error;
|
|
}
|
|
EXPORT_SYMBOL(thaw_bdev);
|
|
|
|
static int blkdev_writepage(struct page *page, struct writeback_control *wbc)
|
|
{
|
|
return block_write_full_page(page, blkdev_get_block, wbc);
|
|
}
|
|
|
|
static int blkdev_readpage(struct file * file, struct page * page)
|
|
{
|
|
return block_read_full_page(page, blkdev_get_block);
|
|
}
|
|
|
|
static void blkdev_readahead(struct readahead_control *rac)
|
|
{
|
|
mpage_readahead(rac, blkdev_get_block);
|
|
}
|
|
|
|
static int blkdev_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
return block_write_begin(mapping, pos, len, flags, pagep,
|
|
blkdev_get_block);
|
|
}
|
|
|
|
static int blkdev_write_end(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
int ret;
|
|
ret = block_write_end(file, mapping, pos, len, copied, page, fsdata);
|
|
|
|
unlock_page(page);
|
|
put_page(page);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* private llseek:
|
|
* for a block special file file_inode(file)->i_size is zero
|
|
* so we compute the size by hand (just as in block_read/write above)
|
|
*/
|
|
static loff_t block_llseek(struct file *file, loff_t offset, int whence)
|
|
{
|
|
struct inode *bd_inode = bdev_file_inode(file);
|
|
loff_t retval;
|
|
|
|
inode_lock(bd_inode);
|
|
retval = fixed_size_llseek(file, offset, whence, i_size_read(bd_inode));
|
|
inode_unlock(bd_inode);
|
|
return retval;
|
|
}
|
|
|
|
int blkdev_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
|
|
{
|
|
struct inode *bd_inode = bdev_file_inode(filp);
|
|
struct block_device *bdev = I_BDEV(bd_inode);
|
|
int error;
|
|
|
|
error = file_write_and_wait_range(filp, start, end);
|
|
if (error)
|
|
return error;
|
|
|
|
/*
|
|
* There is no need to serialise calls to blkdev_issue_flush with
|
|
* i_mutex and doing so causes performance issues with concurrent
|
|
* O_SYNC writers to a block device.
|
|
*/
|
|
error = blkdev_issue_flush(bdev);
|
|
if (error == -EOPNOTSUPP)
|
|
error = 0;
|
|
|
|
return error;
|
|
}
|
|
EXPORT_SYMBOL(blkdev_fsync);
|
|
|
|
/**
|
|
* bdev_read_page() - Start reading a page from a block device
|
|
* @bdev: The device to read the page from
|
|
* @sector: The offset on the device to read the page to (need not be aligned)
|
|
* @page: The page to read
|
|
*
|
|
* On entry, the page should be locked. It will be unlocked when the page
|
|
* has been read. If the block driver implements rw_page synchronously,
|
|
* that will be true on exit from this function, but it need not be.
|
|
*
|
|
* Errors returned by this function are usually "soft", eg out of memory, or
|
|
* queue full; callers should try a different route to read this page rather
|
|
* than propagate an error back up the stack.
|
|
*
|
|
* Return: negative errno if an error occurs, 0 if submission was successful.
|
|
*/
|
|
int bdev_read_page(struct block_device *bdev, sector_t sector,
|
|
struct page *page)
|
|
{
|
|
const struct block_device_operations *ops = bdev->bd_disk->fops;
|
|
int result = -EOPNOTSUPP;
|
|
|
|
if (!ops->rw_page || bdev_get_integrity(bdev))
|
|
return result;
|
|
|
|
result = blk_queue_enter(bdev->bd_disk->queue, 0);
|
|
if (result)
|
|
return result;
|
|
result = ops->rw_page(bdev, sector + get_start_sect(bdev), page,
|
|
REQ_OP_READ);
|
|
blk_queue_exit(bdev->bd_disk->queue);
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* bdev_write_page() - Start writing a page to a block device
|
|
* @bdev: The device to write the page to
|
|
* @sector: The offset on the device to write the page to (need not be aligned)
|
|
* @page: The page to write
|
|
* @wbc: The writeback_control for the write
|
|
*
|
|
* On entry, the page should be locked and not currently under writeback.
|
|
* On exit, if the write started successfully, the page will be unlocked and
|
|
* under writeback. If the write failed already (eg the driver failed to
|
|
* queue the page to the device), the page will still be locked. If the
|
|
* caller is a ->writepage implementation, it will need to unlock the page.
|
|
*
|
|
* Errors returned by this function are usually "soft", eg out of memory, or
|
|
* queue full; callers should try a different route to write this page rather
|
|
* than propagate an error back up the stack.
|
|
*
|
|
* Return: negative errno if an error occurs, 0 if submission was successful.
|
|
*/
|
|
int bdev_write_page(struct block_device *bdev, sector_t sector,
|
|
struct page *page, struct writeback_control *wbc)
|
|
{
|
|
int result;
|
|
const struct block_device_operations *ops = bdev->bd_disk->fops;
|
|
|
|
if (!ops->rw_page || bdev_get_integrity(bdev))
|
|
return -EOPNOTSUPP;
|
|
result = blk_queue_enter(bdev->bd_disk->queue, 0);
|
|
if (result)
|
|
return result;
|
|
|
|
set_page_writeback(page);
|
|
result = ops->rw_page(bdev, sector + get_start_sect(bdev), page,
|
|
REQ_OP_WRITE);
|
|
if (result) {
|
|
end_page_writeback(page);
|
|
} else {
|
|
clean_page_buffers(page);
|
|
unlock_page(page);
|
|
}
|
|
blk_queue_exit(bdev->bd_disk->queue);
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* pseudo-fs
|
|
*/
|
|
|
|
static __cacheline_aligned_in_smp DEFINE_SPINLOCK(bdev_lock);
|
|
static struct kmem_cache * bdev_cachep __read_mostly;
|
|
|
|
static struct inode *bdev_alloc_inode(struct super_block *sb)
|
|
{
|
|
struct bdev_inode *ei = kmem_cache_alloc(bdev_cachep, GFP_KERNEL);
|
|
|
|
if (!ei)
|
|
return NULL;
|
|
memset(&ei->bdev, 0, sizeof(ei->bdev));
|
|
ei->bdev.bd_bdi = &noop_backing_dev_info;
|
|
return &ei->vfs_inode;
|
|
}
|
|
|
|
static void bdev_free_inode(struct inode *inode)
|
|
{
|
|
struct block_device *bdev = I_BDEV(inode);
|
|
|
|
free_percpu(bdev->bd_stats);
|
|
kfree(bdev->bd_meta_info);
|
|
|
|
kmem_cache_free(bdev_cachep, BDEV_I(inode));
|
|
}
|
|
|
|
static void init_once(void *data)
|
|
{
|
|
struct bdev_inode *ei = data;
|
|
|
|
inode_init_once(&ei->vfs_inode);
|
|
}
|
|
|
|
static void bdev_evict_inode(struct inode *inode)
|
|
{
|
|
struct block_device *bdev = &BDEV_I(inode)->bdev;
|
|
truncate_inode_pages_final(&inode->i_data);
|
|
invalidate_inode_buffers(inode); /* is it needed here? */
|
|
clear_inode(inode);
|
|
/* Detach inode from wb early as bdi_put() may free bdi->wb */
|
|
inode_detach_wb(inode);
|
|
if (bdev->bd_bdi != &noop_backing_dev_info) {
|
|
bdi_put(bdev->bd_bdi);
|
|
bdev->bd_bdi = &noop_backing_dev_info;
|
|
}
|
|
}
|
|
|
|
static const struct super_operations bdev_sops = {
|
|
.statfs = simple_statfs,
|
|
.alloc_inode = bdev_alloc_inode,
|
|
.free_inode = bdev_free_inode,
|
|
.drop_inode = generic_delete_inode,
|
|
.evict_inode = bdev_evict_inode,
|
|
};
|
|
|
|
static int bd_init_fs_context(struct fs_context *fc)
|
|
{
|
|
struct pseudo_fs_context *ctx = init_pseudo(fc, BDEVFS_MAGIC);
|
|
if (!ctx)
|
|
return -ENOMEM;
|
|
fc->s_iflags |= SB_I_CGROUPWB;
|
|
ctx->ops = &bdev_sops;
|
|
return 0;
|
|
}
|
|
|
|
static struct file_system_type bd_type = {
|
|
.name = "bdev",
|
|
.init_fs_context = bd_init_fs_context,
|
|
.kill_sb = kill_anon_super,
|
|
};
|
|
|
|
struct super_block *blockdev_superblock __read_mostly;
|
|
EXPORT_SYMBOL_GPL(blockdev_superblock);
|
|
|
|
void __init bdev_cache_init(void)
|
|
{
|
|
int err;
|
|
static struct vfsmount *bd_mnt;
|
|
|
|
bdev_cachep = kmem_cache_create("bdev_cache", sizeof(struct bdev_inode),
|
|
0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
|
|
SLAB_MEM_SPREAD|SLAB_ACCOUNT|SLAB_PANIC),
|
|
init_once);
|
|
err = register_filesystem(&bd_type);
|
|
if (err)
|
|
panic("Cannot register bdev pseudo-fs");
|
|
bd_mnt = kern_mount(&bd_type);
|
|
if (IS_ERR(bd_mnt))
|
|
panic("Cannot create bdev pseudo-fs");
|
|
blockdev_superblock = bd_mnt->mnt_sb; /* For writeback */
|
|
}
|
|
|
|
struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
|
|
{
|
|
struct block_device *bdev;
|
|
struct inode *inode;
|
|
|
|
inode = new_inode(blockdev_superblock);
|
|
if (!inode)
|
|
return NULL;
|
|
inode->i_mode = S_IFBLK;
|
|
inode->i_rdev = 0;
|
|
inode->i_data.a_ops = &def_blk_aops;
|
|
mapping_set_gfp_mask(&inode->i_data, GFP_USER);
|
|
|
|
bdev = I_BDEV(inode);
|
|
mutex_init(&bdev->bd_fsfreeze_mutex);
|
|
spin_lock_init(&bdev->bd_size_lock);
|
|
bdev->bd_disk = disk;
|
|
bdev->bd_partno = partno;
|
|
bdev->bd_inode = inode;
|
|
#ifdef CONFIG_SYSFS
|
|
INIT_LIST_HEAD(&bdev->bd_holder_disks);
|
|
#endif
|
|
bdev->bd_stats = alloc_percpu(struct disk_stats);
|
|
if (!bdev->bd_stats) {
|
|
iput(inode);
|
|
return NULL;
|
|
}
|
|
return bdev;
|
|
}
|
|
|
|
void bdev_add(struct block_device *bdev, dev_t dev)
|
|
{
|
|
bdev->bd_dev = dev;
|
|
bdev->bd_inode->i_rdev = dev;
|
|
bdev->bd_inode->i_ino = dev;
|
|
insert_inode_hash(bdev->bd_inode);
|
|
}
|
|
|
|
static struct block_device *bdget(dev_t dev)
|
|
{
|
|
struct inode *inode;
|
|
|
|
inode = ilookup(blockdev_superblock, dev);
|
|
if (!inode)
|
|
return NULL;
|
|
return &BDEV_I(inode)->bdev;
|
|
}
|
|
|
|
/**
|
|
* bdgrab -- Grab a reference to an already referenced block device
|
|
* @bdev: Block device to grab a reference to.
|
|
*
|
|
* Returns the block_device with an additional reference when successful,
|
|
* or NULL if the inode is already beeing freed.
|
|
*/
|
|
struct block_device *bdgrab(struct block_device *bdev)
|
|
{
|
|
if (!igrab(bdev->bd_inode))
|
|
return NULL;
|
|
return bdev;
|
|
}
|
|
EXPORT_SYMBOL(bdgrab);
|
|
|
|
long nr_blockdev_pages(void)
|
|
{
|
|
struct inode *inode;
|
|
long ret = 0;
|
|
|
|
spin_lock(&blockdev_superblock->s_inode_list_lock);
|
|
list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list)
|
|
ret += inode->i_mapping->nrpages;
|
|
spin_unlock(&blockdev_superblock->s_inode_list_lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
void bdput(struct block_device *bdev)
|
|
{
|
|
iput(bdev->bd_inode);
|
|
}
|
|
EXPORT_SYMBOL(bdput);
|
|
|
|
/**
|
|
* bd_may_claim - test whether a block device can be claimed
|
|
* @bdev: block device of interest
|
|
* @whole: whole block device containing @bdev, may equal @bdev
|
|
* @holder: holder trying to claim @bdev
|
|
*
|
|
* Test whether @bdev can be claimed by @holder.
|
|
*
|
|
* CONTEXT:
|
|
* spin_lock(&bdev_lock).
|
|
*
|
|
* RETURNS:
|
|
* %true if @bdev can be claimed, %false otherwise.
|
|
*/
|
|
static bool bd_may_claim(struct block_device *bdev, struct block_device *whole,
|
|
void *holder)
|
|
{
|
|
if (bdev->bd_holder == holder)
|
|
return true; /* already a holder */
|
|
else if (bdev->bd_holder != NULL)
|
|
return false; /* held by someone else */
|
|
else if (whole == bdev)
|
|
return true; /* is a whole device which isn't held */
|
|
|
|
else if (whole->bd_holder == bd_may_claim)
|
|
return true; /* is a partition of a device that is being partitioned */
|
|
else if (whole->bd_holder != NULL)
|
|
return false; /* is a partition of a held device */
|
|
else
|
|
return true; /* is a partition of an un-held device */
|
|
}
|
|
|
|
/**
|
|
* bd_prepare_to_claim - claim a block device
|
|
* @bdev: block device of interest
|
|
* @holder: holder trying to claim @bdev
|
|
*
|
|
* Claim @bdev. This function fails if @bdev is already claimed by another
|
|
* holder and waits if another claiming is in progress. return, the caller
|
|
* has ownership of bd_claiming and bd_holder[s].
|
|
*
|
|
* RETURNS:
|
|
* 0 if @bdev can be claimed, -EBUSY otherwise.
|
|
*/
|
|
int bd_prepare_to_claim(struct block_device *bdev, void *holder)
|
|
{
|
|
struct block_device *whole = bdev_whole(bdev);
|
|
|
|
if (WARN_ON_ONCE(!holder))
|
|
return -EINVAL;
|
|
retry:
|
|
spin_lock(&bdev_lock);
|
|
/* if someone else claimed, fail */
|
|
if (!bd_may_claim(bdev, whole, holder)) {
|
|
spin_unlock(&bdev_lock);
|
|
return -EBUSY;
|
|
}
|
|
|
|
/* if claiming is already in progress, wait for it to finish */
|
|
if (whole->bd_claiming) {
|
|
wait_queue_head_t *wq = bit_waitqueue(&whole->bd_claiming, 0);
|
|
DEFINE_WAIT(wait);
|
|
|
|
prepare_to_wait(wq, &wait, TASK_UNINTERRUPTIBLE);
|
|
spin_unlock(&bdev_lock);
|
|
schedule();
|
|
finish_wait(wq, &wait);
|
|
goto retry;
|
|
}
|
|
|
|
/* yay, all mine */
|
|
whole->bd_claiming = holder;
|
|
spin_unlock(&bdev_lock);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(bd_prepare_to_claim); /* only for the loop driver */
|
|
|
|
static void bd_clear_claiming(struct block_device *whole, void *holder)
|
|
{
|
|
lockdep_assert_held(&bdev_lock);
|
|
/* tell others that we're done */
|
|
BUG_ON(whole->bd_claiming != holder);
|
|
whole->bd_claiming = NULL;
|
|
wake_up_bit(&whole->bd_claiming, 0);
|
|
}
|
|
|
|
/**
|
|
* bd_finish_claiming - finish claiming of a block device
|
|
* @bdev: block device of interest
|
|
* @holder: holder that has claimed @bdev
|
|
*
|
|
* Finish exclusive open of a block device. Mark the device as exlusively
|
|
* open by the holder and wake up all waiters for exclusive open to finish.
|
|
*/
|
|
static void bd_finish_claiming(struct block_device *bdev, void *holder)
|
|
{
|
|
struct block_device *whole = bdev_whole(bdev);
|
|
|
|
spin_lock(&bdev_lock);
|
|
BUG_ON(!bd_may_claim(bdev, whole, holder));
|
|
/*
|
|
* Note that for a whole device bd_holders will be incremented twice,
|
|
* and bd_holder will be set to bd_may_claim before being set to holder
|
|
*/
|
|
whole->bd_holders++;
|
|
whole->bd_holder = bd_may_claim;
|
|
bdev->bd_holders++;
|
|
bdev->bd_holder = holder;
|
|
bd_clear_claiming(whole, holder);
|
|
spin_unlock(&bdev_lock);
|
|
}
|
|
|
|
/**
|
|
* bd_abort_claiming - abort claiming of a block device
|
|
* @bdev: block device of interest
|
|
* @holder: holder that has claimed @bdev
|
|
*
|
|
* Abort claiming of a block device when the exclusive open failed. This can be
|
|
* also used when exclusive open is not actually desired and we just needed
|
|
* to block other exclusive openers for a while.
|
|
*/
|
|
void bd_abort_claiming(struct block_device *bdev, void *holder)
|
|
{
|
|
spin_lock(&bdev_lock);
|
|
bd_clear_claiming(bdev_whole(bdev), holder);
|
|
spin_unlock(&bdev_lock);
|
|
}
|
|
EXPORT_SYMBOL(bd_abort_claiming);
|
|
|
|
#ifdef CONFIG_SYSFS
|
|
struct bd_holder_disk {
|
|
struct list_head list;
|
|
struct gendisk *disk;
|
|
int refcnt;
|
|
};
|
|
|
|
static struct bd_holder_disk *bd_find_holder_disk(struct block_device *bdev,
|
|
struct gendisk *disk)
|
|
{
|
|
struct bd_holder_disk *holder;
|
|
|
|
list_for_each_entry(holder, &bdev->bd_holder_disks, list)
|
|
if (holder->disk == disk)
|
|
return holder;
|
|
return NULL;
|
|
}
|
|
|
|
static int add_symlink(struct kobject *from, struct kobject *to)
|
|
{
|
|
return sysfs_create_link(from, to, kobject_name(to));
|
|
}
|
|
|
|
static void del_symlink(struct kobject *from, struct kobject *to)
|
|
{
|
|
sysfs_remove_link(from, kobject_name(to));
|
|
}
|
|
|
|
/**
|
|
* bd_link_disk_holder - create symlinks between holding disk and slave bdev
|
|
* @bdev: the claimed slave bdev
|
|
* @disk: the holding disk
|
|
*
|
|
* DON'T USE THIS UNLESS YOU'RE ALREADY USING IT.
|
|
*
|
|
* This functions creates the following sysfs symlinks.
|
|
*
|
|
* - from "slaves" directory of the holder @disk to the claimed @bdev
|
|
* - from "holders" directory of the @bdev to the holder @disk
|
|
*
|
|
* For example, if /dev/dm-0 maps to /dev/sda and disk for dm-0 is
|
|
* passed to bd_link_disk_holder(), then:
|
|
*
|
|
* /sys/block/dm-0/slaves/sda --> /sys/block/sda
|
|
* /sys/block/sda/holders/dm-0 --> /sys/block/dm-0
|
|
*
|
|
* The caller must have claimed @bdev before calling this function and
|
|
* ensure that both @bdev and @disk are valid during the creation and
|
|
* lifetime of these symlinks.
|
|
*
|
|
* CONTEXT:
|
|
* Might sleep.
|
|
*
|
|
* RETURNS:
|
|
* 0 on success, -errno on failure.
|
|
*/
|
|
int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk)
|
|
{
|
|
struct bd_holder_disk *holder;
|
|
int ret = 0;
|
|
|
|
mutex_lock(&bdev->bd_disk->open_mutex);
|
|
|
|
WARN_ON_ONCE(!bdev->bd_holder);
|
|
|
|
/* FIXME: remove the following once add_disk() handles errors */
|
|
if (WARN_ON(!disk->slave_dir || !bdev->bd_holder_dir))
|
|
goto out_unlock;
|
|
|
|
holder = bd_find_holder_disk(bdev, disk);
|
|
if (holder) {
|
|
holder->refcnt++;
|
|
goto out_unlock;
|
|
}
|
|
|
|
holder = kzalloc(sizeof(*holder), GFP_KERNEL);
|
|
if (!holder) {
|
|
ret = -ENOMEM;
|
|
goto out_unlock;
|
|
}
|
|
|
|
INIT_LIST_HEAD(&holder->list);
|
|
holder->disk = disk;
|
|
holder->refcnt = 1;
|
|
|
|
ret = add_symlink(disk->slave_dir, bdev_kobj(bdev));
|
|
if (ret)
|
|
goto out_free;
|
|
|
|
ret = add_symlink(bdev->bd_holder_dir, &disk_to_dev(disk)->kobj);
|
|
if (ret)
|
|
goto out_del;
|
|
/*
|
|
* bdev could be deleted beneath us which would implicitly destroy
|
|
* the holder directory. Hold on to it.
|
|
*/
|
|
kobject_get(bdev->bd_holder_dir);
|
|
|
|
list_add(&holder->list, &bdev->bd_holder_disks);
|
|
goto out_unlock;
|
|
|
|
out_del:
|
|
del_symlink(disk->slave_dir, bdev_kobj(bdev));
|
|
out_free:
|
|
kfree(holder);
|
|
out_unlock:
|
|
mutex_unlock(&bdev->bd_disk->open_mutex);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(bd_link_disk_holder);
|
|
|
|
/**
|
|
* bd_unlink_disk_holder - destroy symlinks created by bd_link_disk_holder()
|
|
* @bdev: the calimed slave bdev
|
|
* @disk: the holding disk
|
|
*
|
|
* DON'T USE THIS UNLESS YOU'RE ALREADY USING IT.
|
|
*
|
|
* CONTEXT:
|
|
* Might sleep.
|
|
*/
|
|
void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk)
|
|
{
|
|
struct bd_holder_disk *holder;
|
|
|
|
mutex_lock(&bdev->bd_disk->open_mutex);
|
|
|
|
holder = bd_find_holder_disk(bdev, disk);
|
|
|
|
if (!WARN_ON_ONCE(holder == NULL) && !--holder->refcnt) {
|
|
del_symlink(disk->slave_dir, bdev_kobj(bdev));
|
|
del_symlink(bdev->bd_holder_dir, &disk_to_dev(disk)->kobj);
|
|
kobject_put(bdev->bd_holder_dir);
|
|
list_del_init(&holder->list);
|
|
kfree(holder);
|
|
}
|
|
|
|
mutex_unlock(&bdev->bd_disk->open_mutex);
|
|
}
|
|
EXPORT_SYMBOL_GPL(bd_unlink_disk_holder);
|
|
#endif
|
|
|
|
static void blkdev_flush_mapping(struct block_device *bdev)
|
|
{
|
|
WARN_ON_ONCE(bdev->bd_holders);
|
|
sync_blockdev(bdev);
|
|
kill_bdev(bdev);
|
|
bdev_write_inode(bdev);
|
|
}
|
|
|
|
static int blkdev_get_whole(struct block_device *bdev, fmode_t mode)
|
|
{
|
|
struct gendisk *disk = bdev->bd_disk;
|
|
int ret = 0;
|
|
|
|
if (disk->fops->open) {
|
|
ret = disk->fops->open(bdev, mode);
|
|
if (ret) {
|
|
/* avoid ghost partitions on a removed medium */
|
|
if (ret == -ENOMEDIUM &&
|
|
test_bit(GD_NEED_PART_SCAN, &disk->state))
|
|
bdev_disk_changed(disk, true);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
if (!bdev->bd_openers) {
|
|
set_init_blocksize(bdev);
|
|
if (bdev->bd_bdi == &noop_backing_dev_info)
|
|
bdev->bd_bdi = bdi_get(disk->queue->backing_dev_info);
|
|
}
|
|
if (test_bit(GD_NEED_PART_SCAN, &disk->state))
|
|
bdev_disk_changed(disk, false);
|
|
bdev->bd_openers++;
|
|
return 0;;
|
|
}
|
|
|
|
static void blkdev_put_whole(struct block_device *bdev, fmode_t mode)
|
|
{
|
|
if (!--bdev->bd_openers)
|
|
blkdev_flush_mapping(bdev);
|
|
if (bdev->bd_disk->fops->release)
|
|
bdev->bd_disk->fops->release(bdev->bd_disk, mode);
|
|
}
|
|
|
|
static int blkdev_get_part(struct block_device *part, fmode_t mode)
|
|
{
|
|
struct gendisk *disk = part->bd_disk;
|
|
struct block_device *whole;
|
|
int ret;
|
|
|
|
if (part->bd_openers)
|
|
goto done;
|
|
|
|
whole = bdgrab(disk->part0);
|
|
ret = blkdev_get_whole(whole, mode);
|
|
if (ret)
|
|
goto out_put_whole;
|
|
|
|
ret = -ENXIO;
|
|
if (!bdev_nr_sectors(part))
|
|
goto out_blkdev_put;
|
|
|
|
disk->open_partitions++;
|
|
set_init_blocksize(part);
|
|
if (part->bd_bdi == &noop_backing_dev_info)
|
|
part->bd_bdi = bdi_get(disk->queue->backing_dev_info);
|
|
done:
|
|
part->bd_openers++;
|
|
return 0;
|
|
|
|
out_blkdev_put:
|
|
blkdev_put_whole(whole, mode);
|
|
out_put_whole:
|
|
bdput(whole);
|
|
return ret;
|
|
}
|
|
|
|
static void blkdev_put_part(struct block_device *part, fmode_t mode)
|
|
{
|
|
struct block_device *whole = bdev_whole(part);
|
|
|
|
if (--part->bd_openers)
|
|
return;
|
|
blkdev_flush_mapping(part);
|
|
whole->bd_disk->open_partitions--;
|
|
blkdev_put_whole(whole, mode);
|
|
bdput(whole);
|
|
}
|
|
|
|
struct block_device *blkdev_get_no_open(dev_t dev)
|
|
{
|
|
struct block_device *bdev;
|
|
struct gendisk *disk;
|
|
|
|
bdev = bdget(dev);
|
|
if (!bdev) {
|
|
blk_request_module(dev);
|
|
bdev = bdget(dev);
|
|
if (!bdev)
|
|
return NULL;
|
|
}
|
|
|
|
disk = bdev->bd_disk;
|
|
if (!kobject_get_unless_zero(&disk_to_dev(disk)->kobj))
|
|
goto bdput;
|
|
if ((disk->flags & (GENHD_FL_UP | GENHD_FL_HIDDEN)) != GENHD_FL_UP)
|
|
goto put_disk;
|
|
if (!try_module_get(bdev->bd_disk->fops->owner))
|
|
goto put_disk;
|
|
return bdev;
|
|
put_disk:
|
|
put_disk(disk);
|
|
bdput:
|
|
bdput(bdev);
|
|
return NULL;
|
|
}
|
|
|
|
void blkdev_put_no_open(struct block_device *bdev)
|
|
{
|
|
module_put(bdev->bd_disk->fops->owner);
|
|
put_disk(bdev->bd_disk);
|
|
bdput(bdev);
|
|
}
|
|
|
|
/**
|
|
* blkdev_get_by_dev - open a block device by device number
|
|
* @dev: device number of block device to open
|
|
* @mode: FMODE_* mask
|
|
* @holder: exclusive holder identifier
|
|
*
|
|
* Open the block device described by device number @dev. If @mode includes
|
|
* %FMODE_EXCL, the block device is opened with exclusive access. Specifying
|
|
* %FMODE_EXCL with a %NULL @holder is invalid. Exclusive opens may nest for
|
|
* the same @holder.
|
|
*
|
|
* Use this interface ONLY if you really do not have anything better - i.e. when
|
|
* you are behind a truly sucky interface and all you are given is a device
|
|
* number. Everything else should use blkdev_get_by_path().
|
|
*
|
|
* CONTEXT:
|
|
* Might sleep.
|
|
*
|
|
* RETURNS:
|
|
* Reference to the block_device on success, ERR_PTR(-errno) on failure.
|
|
*/
|
|
struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode, void *holder)
|
|
{
|
|
bool unblock_events = true;
|
|
struct block_device *bdev;
|
|
struct gendisk *disk;
|
|
int ret;
|
|
|
|
ret = devcgroup_check_permission(DEVCG_DEV_BLOCK,
|
|
MAJOR(dev), MINOR(dev),
|
|
((mode & FMODE_READ) ? DEVCG_ACC_READ : 0) |
|
|
((mode & FMODE_WRITE) ? DEVCG_ACC_WRITE : 0));
|
|
if (ret)
|
|
return ERR_PTR(ret);
|
|
|
|
bdev = blkdev_get_no_open(dev);
|
|
if (!bdev)
|
|
return ERR_PTR(-ENXIO);
|
|
disk = bdev->bd_disk;
|
|
|
|
if (mode & FMODE_EXCL) {
|
|
ret = bd_prepare_to_claim(bdev, holder);
|
|
if (ret)
|
|
goto put_blkdev;
|
|
}
|
|
|
|
disk_block_events(disk);
|
|
|
|
mutex_lock(&disk->open_mutex);
|
|
ret = -ENXIO;
|
|
if (!(disk->flags & GENHD_FL_UP))
|
|
goto abort_claiming;
|
|
if (bdev_is_partition(bdev))
|
|
ret = blkdev_get_part(bdev, mode);
|
|
else
|
|
ret = blkdev_get_whole(bdev, mode);
|
|
if (ret)
|
|
goto abort_claiming;
|
|
if (mode & FMODE_EXCL) {
|
|
bd_finish_claiming(bdev, holder);
|
|
|
|
/*
|
|
* Block event polling for write claims if requested. Any write
|
|
* holder makes the write_holder state stick until all are
|
|
* released. This is good enough and tracking individual
|
|
* writeable reference is too fragile given the way @mode is
|
|
* used in blkdev_get/put().
|
|
*/
|
|
if ((mode & FMODE_WRITE) && !bdev->bd_write_holder &&
|
|
(disk->flags & GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE)) {
|
|
bdev->bd_write_holder = true;
|
|
unblock_events = false;
|
|
}
|
|
}
|
|
mutex_unlock(&disk->open_mutex);
|
|
|
|
if (unblock_events)
|
|
disk_unblock_events(disk);
|
|
return bdev;
|
|
|
|
abort_claiming:
|
|
if (mode & FMODE_EXCL)
|
|
bd_abort_claiming(bdev, holder);
|
|
mutex_unlock(&disk->open_mutex);
|
|
disk_unblock_events(disk);
|
|
put_blkdev:
|
|
blkdev_put_no_open(bdev);
|
|
return ERR_PTR(ret);
|
|
}
|
|
EXPORT_SYMBOL(blkdev_get_by_dev);
|
|
|
|
/**
|
|
* blkdev_get_by_path - open a block device by name
|
|
* @path: path to the block device to open
|
|
* @mode: FMODE_* mask
|
|
* @holder: exclusive holder identifier
|
|
*
|
|
* Open the block device described by the device file at @path. If @mode
|
|
* includes %FMODE_EXCL, the block device is opened with exclusive access.
|
|
* Specifying %FMODE_EXCL with a %NULL @holder is invalid. Exclusive opens may
|
|
* nest for the same @holder.
|
|
*
|
|
* CONTEXT:
|
|
* Might sleep.
|
|
*
|
|
* RETURNS:
|
|
* Reference to the block_device on success, ERR_PTR(-errno) on failure.
|
|
*/
|
|
struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
|
|
void *holder)
|
|
{
|
|
struct block_device *bdev;
|
|
dev_t dev;
|
|
int error;
|
|
|
|
error = lookup_bdev(path, &dev);
|
|
if (error)
|
|
return ERR_PTR(error);
|
|
|
|
bdev = blkdev_get_by_dev(dev, mode, holder);
|
|
if (!IS_ERR(bdev) && (mode & FMODE_WRITE) && bdev_read_only(bdev)) {
|
|
blkdev_put(bdev, mode);
|
|
return ERR_PTR(-EACCES);
|
|
}
|
|
|
|
return bdev;
|
|
}
|
|
EXPORT_SYMBOL(blkdev_get_by_path);
|
|
|
|
static int blkdev_open(struct inode * inode, struct file * filp)
|
|
{
|
|
struct block_device *bdev;
|
|
|
|
/*
|
|
* Preserve backwards compatibility and allow large file access
|
|
* even if userspace doesn't ask for it explicitly. Some mkfs
|
|
* binary needs it. We might want to drop this workaround
|
|
* during an unstable branch.
|
|
*/
|
|
filp->f_flags |= O_LARGEFILE;
|
|
|
|
filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC;
|
|
|
|
if (filp->f_flags & O_NDELAY)
|
|
filp->f_mode |= FMODE_NDELAY;
|
|
if (filp->f_flags & O_EXCL)
|
|
filp->f_mode |= FMODE_EXCL;
|
|
if ((filp->f_flags & O_ACCMODE) == 3)
|
|
filp->f_mode |= FMODE_WRITE_IOCTL;
|
|
|
|
bdev = blkdev_get_by_dev(inode->i_rdev, filp->f_mode, filp);
|
|
if (IS_ERR(bdev))
|
|
return PTR_ERR(bdev);
|
|
filp->f_mapping = bdev->bd_inode->i_mapping;
|
|
filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping);
|
|
return 0;
|
|
}
|
|
|
|
void blkdev_put(struct block_device *bdev, fmode_t mode)
|
|
{
|
|
struct gendisk *disk = bdev->bd_disk;
|
|
|
|
/*
|
|
* Sync early if it looks like we're the last one. If someone else
|
|
* opens the block device between now and the decrement of bd_openers
|
|
* then we did a sync that we didn't need to, but that's not the end
|
|
* of the world and we want to avoid long (could be several minute)
|
|
* syncs while holding the mutex.
|
|
*/
|
|
if (bdev->bd_openers == 1)
|
|
sync_blockdev(bdev);
|
|
|
|
mutex_lock(&disk->open_mutex);
|
|
if (mode & FMODE_EXCL) {
|
|
struct block_device *whole = bdev_whole(bdev);
|
|
bool bdev_free;
|
|
|
|
/*
|
|
* Release a claim on the device. The holder fields
|
|
* are protected with bdev_lock. open_mutex is to
|
|
* synchronize disk_holder unlinking.
|
|
*/
|
|
spin_lock(&bdev_lock);
|
|
|
|
WARN_ON_ONCE(--bdev->bd_holders < 0);
|
|
WARN_ON_ONCE(--whole->bd_holders < 0);
|
|
|
|
if ((bdev_free = !bdev->bd_holders))
|
|
bdev->bd_holder = NULL;
|
|
if (!whole->bd_holders)
|
|
whole->bd_holder = NULL;
|
|
|
|
spin_unlock(&bdev_lock);
|
|
|
|
/*
|
|
* If this was the last claim, remove holder link and
|
|
* unblock evpoll if it was a write holder.
|
|
*/
|
|
if (bdev_free && bdev->bd_write_holder) {
|
|
disk_unblock_events(disk);
|
|
bdev->bd_write_holder = false;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Trigger event checking and tell drivers to flush MEDIA_CHANGE
|
|
* event. This is to ensure detection of media removal commanded
|
|
* from userland - e.g. eject(1).
|
|
*/
|
|
disk_flush_events(disk, DISK_EVENT_MEDIA_CHANGE);
|
|
|
|
if (bdev_is_partition(bdev))
|
|
blkdev_put_part(bdev, mode);
|
|
else
|
|
blkdev_put_whole(bdev, mode);
|
|
mutex_unlock(&disk->open_mutex);
|
|
|
|
blkdev_put_no_open(bdev);
|
|
}
|
|
EXPORT_SYMBOL(blkdev_put);
|
|
|
|
static int blkdev_close(struct inode * inode, struct file * filp)
|
|
{
|
|
struct block_device *bdev = I_BDEV(bdev_file_inode(filp));
|
|
blkdev_put(bdev, filp->f_mode);
|
|
return 0;
|
|
}
|
|
|
|
static long block_ioctl(struct file *file, unsigned cmd, unsigned long arg)
|
|
{
|
|
struct block_device *bdev = I_BDEV(bdev_file_inode(file));
|
|
fmode_t mode = file->f_mode;
|
|
|
|
/*
|
|
* O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have
|
|
* to updated it before every ioctl.
|
|
*/
|
|
if (file->f_flags & O_NDELAY)
|
|
mode |= FMODE_NDELAY;
|
|
else
|
|
mode &= ~FMODE_NDELAY;
|
|
|
|
return blkdev_ioctl(bdev, mode, cmd, arg);
|
|
}
|
|
|
|
/*
|
|
* Write data to the block device. Only intended for the block device itself
|
|
* and the raw driver which basically is a fake block device.
|
|
*
|
|
* Does not take i_mutex for the write and thus is not for general purpose
|
|
* use.
|
|
*/
|
|
static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *bd_inode = bdev_file_inode(file);
|
|
loff_t size = i_size_read(bd_inode);
|
|
struct blk_plug plug;
|
|
size_t shorted = 0;
|
|
ssize_t ret;
|
|
|
|
if (bdev_read_only(I_BDEV(bd_inode)))
|
|
return -EPERM;
|
|
|
|
if (IS_SWAPFILE(bd_inode) && !is_hibernate_resume_dev(bd_inode->i_rdev))
|
|
return -ETXTBSY;
|
|
|
|
if (!iov_iter_count(from))
|
|
return 0;
|
|
|
|
if (iocb->ki_pos >= size)
|
|
return -ENOSPC;
|
|
|
|
if ((iocb->ki_flags & (IOCB_NOWAIT | IOCB_DIRECT)) == IOCB_NOWAIT)
|
|
return -EOPNOTSUPP;
|
|
|
|
size -= iocb->ki_pos;
|
|
if (iov_iter_count(from) > size) {
|
|
shorted = iov_iter_count(from) - size;
|
|
iov_iter_truncate(from, size);
|
|
}
|
|
|
|
blk_start_plug(&plug);
|
|
ret = __generic_file_write_iter(iocb, from);
|
|
if (ret > 0)
|
|
ret = generic_write_sync(iocb, ret);
|
|
iov_iter_reexpand(from, iov_iter_count(from) + shorted);
|
|
blk_finish_plug(&plug);
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *bd_inode = bdev_file_inode(file);
|
|
loff_t size = i_size_read(bd_inode);
|
|
loff_t pos = iocb->ki_pos;
|
|
size_t shorted = 0;
|
|
ssize_t ret;
|
|
|
|
if (pos >= size)
|
|
return 0;
|
|
|
|
size -= pos;
|
|
if (iov_iter_count(to) > size) {
|
|
shorted = iov_iter_count(to) - size;
|
|
iov_iter_truncate(to, size);
|
|
}
|
|
|
|
ret = generic_file_read_iter(iocb, to);
|
|
iov_iter_reexpand(to, iov_iter_count(to) + shorted);
|
|
return ret;
|
|
}
|
|
|
|
static int blkdev_writepages(struct address_space *mapping,
|
|
struct writeback_control *wbc)
|
|
{
|
|
return generic_writepages(mapping, wbc);
|
|
}
|
|
|
|
static const struct address_space_operations def_blk_aops = {
|
|
.set_page_dirty = __set_page_dirty_buffers,
|
|
.readpage = blkdev_readpage,
|
|
.readahead = blkdev_readahead,
|
|
.writepage = blkdev_writepage,
|
|
.write_begin = blkdev_write_begin,
|
|
.write_end = blkdev_write_end,
|
|
.writepages = blkdev_writepages,
|
|
.direct_IO = blkdev_direct_IO,
|
|
.migratepage = buffer_migrate_page_norefs,
|
|
.is_dirty_writeback = buffer_check_dirty_writeback,
|
|
};
|
|
|
|
#define BLKDEV_FALLOC_FL_SUPPORTED \
|
|
(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
|
|
FALLOC_FL_ZERO_RANGE | FALLOC_FL_NO_HIDE_STALE)
|
|
|
|
static long blkdev_fallocate(struct file *file, int mode, loff_t start,
|
|
loff_t len)
|
|
{
|
|
struct block_device *bdev = I_BDEV(bdev_file_inode(file));
|
|
loff_t end = start + len - 1;
|
|
loff_t isize;
|
|
int error;
|
|
|
|
/* Fail if we don't recognize the flags. */
|
|
if (mode & ~BLKDEV_FALLOC_FL_SUPPORTED)
|
|
return -EOPNOTSUPP;
|
|
|
|
/* Don't go off the end of the device. */
|
|
isize = i_size_read(bdev->bd_inode);
|
|
if (start >= isize)
|
|
return -EINVAL;
|
|
if (end >= isize) {
|
|
if (mode & FALLOC_FL_KEEP_SIZE) {
|
|
len = isize - start;
|
|
end = start + len - 1;
|
|
} else
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* Don't allow IO that isn't aligned to logical block size.
|
|
*/
|
|
if ((start | len) & (bdev_logical_block_size(bdev) - 1))
|
|
return -EINVAL;
|
|
|
|
/* Invalidate the page cache, including dirty pages. */
|
|
error = truncate_bdev_range(bdev, file->f_mode, start, end);
|
|
if (error)
|
|
return error;
|
|
|
|
switch (mode) {
|
|
case FALLOC_FL_ZERO_RANGE:
|
|
case FALLOC_FL_ZERO_RANGE | FALLOC_FL_KEEP_SIZE:
|
|
error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9,
|
|
GFP_KERNEL, BLKDEV_ZERO_NOUNMAP);
|
|
break;
|
|
case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE:
|
|
error = blkdev_issue_zeroout(bdev, start >> 9, len >> 9,
|
|
GFP_KERNEL, BLKDEV_ZERO_NOFALLBACK);
|
|
break;
|
|
case FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE | FALLOC_FL_NO_HIDE_STALE:
|
|
error = blkdev_issue_discard(bdev, start >> 9, len >> 9,
|
|
GFP_KERNEL, 0);
|
|
break;
|
|
default:
|
|
return -EOPNOTSUPP;
|
|
}
|
|
if (error)
|
|
return error;
|
|
|
|
/*
|
|
* Invalidate the page cache again; if someone wandered in and dirtied
|
|
* a page, we just discard it - userspace has no way of knowing whether
|
|
* the write happened before or after discard completing...
|
|
*/
|
|
return truncate_bdev_range(bdev, file->f_mode, start, end);
|
|
}
|
|
|
|
const struct file_operations def_blk_fops = {
|
|
.open = blkdev_open,
|
|
.release = blkdev_close,
|
|
.llseek = block_llseek,
|
|
.read_iter = blkdev_read_iter,
|
|
.write_iter = blkdev_write_iter,
|
|
.iopoll = blkdev_iopoll,
|
|
.mmap = generic_file_mmap,
|
|
.fsync = blkdev_fsync,
|
|
.unlocked_ioctl = block_ioctl,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = compat_blkdev_ioctl,
|
|
#endif
|
|
.splice_read = generic_file_splice_read,
|
|
.splice_write = iter_file_splice_write,
|
|
.fallocate = blkdev_fallocate,
|
|
};
|
|
|
|
/**
|
|
* lookup_bdev - lookup a struct block_device by name
|
|
* @pathname: special file representing the block device
|
|
* @dev: return value of the block device's dev_t
|
|
*
|
|
* Get a reference to the blockdevice at @pathname in the current
|
|
* namespace if possible and return it. Return ERR_PTR(error)
|
|
* otherwise.
|
|
*/
|
|
int lookup_bdev(const char *pathname, dev_t *dev)
|
|
{
|
|
struct inode *inode;
|
|
struct path path;
|
|
int error;
|
|
|
|
if (!pathname || !*pathname)
|
|
return -EINVAL;
|
|
|
|
error = kern_path(pathname, LOOKUP_FOLLOW, &path);
|
|
if (error)
|
|
return error;
|
|
|
|
inode = d_backing_inode(path.dentry);
|
|
error = -ENOTBLK;
|
|
if (!S_ISBLK(inode->i_mode))
|
|
goto out_path_put;
|
|
error = -EACCES;
|
|
if (!may_open_dev(&path))
|
|
goto out_path_put;
|
|
|
|
*dev = inode->i_rdev;
|
|
error = 0;
|
|
out_path_put:
|
|
path_put(&path);
|
|
return error;
|
|
}
|
|
EXPORT_SYMBOL(lookup_bdev);
|
|
|
|
int __invalidate_device(struct block_device *bdev, bool kill_dirty)
|
|
{
|
|
struct super_block *sb = get_super(bdev);
|
|
int res = 0;
|
|
|
|
if (sb) {
|
|
/*
|
|
* no need to lock the super, get_super holds the
|
|
* read mutex so the filesystem cannot go away
|
|
* under us (->put_super runs with the write lock
|
|
* hold).
|
|
*/
|
|
shrink_dcache_sb(sb);
|
|
res = invalidate_inodes(sb, kill_dirty);
|
|
drop_super(sb);
|
|
}
|
|
invalidate_bdev(bdev);
|
|
return res;
|
|
}
|
|
EXPORT_SYMBOL(__invalidate_device);
|
|
|
|
void iterate_bdevs(void (*func)(struct block_device *, void *), void *arg)
|
|
{
|
|
struct inode *inode, *old_inode = NULL;
|
|
|
|
spin_lock(&blockdev_superblock->s_inode_list_lock);
|
|
list_for_each_entry(inode, &blockdev_superblock->s_inodes, i_sb_list) {
|
|
struct address_space *mapping = inode->i_mapping;
|
|
struct block_device *bdev;
|
|
|
|
spin_lock(&inode->i_lock);
|
|
if (inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW) ||
|
|
mapping->nrpages == 0) {
|
|
spin_unlock(&inode->i_lock);
|
|
continue;
|
|
}
|
|
__iget(inode);
|
|
spin_unlock(&inode->i_lock);
|
|
spin_unlock(&blockdev_superblock->s_inode_list_lock);
|
|
/*
|
|
* We hold a reference to 'inode' so it couldn't have been
|
|
* removed from s_inodes list while we dropped the
|
|
* s_inode_list_lock We cannot iput the inode now as we can
|
|
* be holding the last reference and we cannot iput it under
|
|
* s_inode_list_lock. So we keep the reference and iput it
|
|
* later.
|
|
*/
|
|
iput(old_inode);
|
|
old_inode = inode;
|
|
bdev = I_BDEV(inode);
|
|
|
|
mutex_lock(&bdev->bd_disk->open_mutex);
|
|
if (bdev->bd_openers)
|
|
func(bdev, arg);
|
|
mutex_unlock(&bdev->bd_disk->open_mutex);
|
|
|
|
spin_lock(&blockdev_superblock->s_inode_list_lock);
|
|
}
|
|
spin_unlock(&blockdev_superblock->s_inode_list_lock);
|
|
iput(old_inode);
|
|
}
|