diff mbox series

[vfs.all,04/26] block: prevent direct access of bd_inode

Message ID 20240406090930.2252838-5-yukuai1@huaweicloud.com (mailing list archive)
State New, archived
Headers show
Series fs & block: remove bdev->bd_inode | expand

Commit Message

Yu Kuai April 6, 2024, 9:09 a.m. UTC 
From: Yu Kuai <yukuai3@huawei.com>

Add helpers to access bd_inode, prepare to remove the field 'bd_inode'
after removing all the access from filesystems and drivers.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
---
 block/bdev.c            | 58 +++++++++++++++++++++++++++--------------
 block/blk-zoned.c       |  4 +--
 block/blk.h             |  2 ++
 block/fops.c            |  2 +-
 block/genhd.c           |  9 ++++---
 block/ioctl.c           |  8 +++---
 block/partitions/core.c |  8 +++---
 7 files changed, 56 insertions(+), 35 deletions(-)

Comments

Al Viro April 7, 2024, 2:22 a.m. UTC | #1 
On Sat, Apr 06, 2024 at 05:09:08PM +0800, Yu Kuai wrote:
> @@ -669,7 +669,7 @@ static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
>  {
>  	struct file *file = iocb->ki_filp;
>  	struct block_device *bdev = I_BDEV(file->f_mapping->host);
> -	struct inode *bd_inode = bdev->bd_inode;
> +	struct inode *bd_inode = bdev_inode(bdev);

What you want here is this:

	struct inode *bd_inode = file->f_mapping->host;
	struct block_device *bdev = I_BDEV(bd_inode);


> --- a/block/ioctl.c
> +++ b/block/ioctl.c
> @@ -97,7 +97,7 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
>  {
>  	uint64_t range[2];
>  	uint64_t start, len;
> -	struct inode *inode = bdev->bd_inode;
> +	struct inode *inode = bdev_inode(bdev);
>  	int err;

The uses of 'inode' in this function are
        filemap_invalidate_lock(inode->i_mapping);
and
        filemap_invalidate_unlock(inode->i_mapping);

IOW, you want bdev_mapping(bdev), not bdev_inode(bdev).

> @@ -166,7 +166,7 @@ static int blk_ioctl_zeroout(struct block_device *bdev, blk_mode_t mode,
>  {
>  	uint64_t range[2];
>  	uint64_t start, end, len;
> -	struct inode *inode = bdev->bd_inode;
> +	struct inode *inode = bdev_inode(bdev);

Same story.
Yu Kuai April 7, 2024, 2:37 a.m. UTC | #2 
Hi,

在 2024/04/07 10:22, Al Viro 写道:
> On Sat, Apr 06, 2024 at 05:09:08PM +0800, Yu Kuai wrote:
>> @@ -669,7 +669,7 @@ static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
>>   {
>>   	struct file *file = iocb->ki_filp;
>>   	struct block_device *bdev = I_BDEV(file->f_mapping->host);
>> -	struct inode *bd_inode = bdev->bd_inode;
>> +	struct inode *bd_inode = bdev_inode(bdev);
> 
> What you want here is this:
> 
> 	struct inode *bd_inode = file->f_mapping->host;
> 	struct block_device *bdev = I_BDEV(bd_inode);

Yes, this way is better, logically.
> 
> 
>> --- a/block/ioctl.c
>> +++ b/block/ioctl.c
>> @@ -97,7 +97,7 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
>>   {
>>   	uint64_t range[2];
>>   	uint64_t start, len;
>> -	struct inode *inode = bdev->bd_inode;
>> +	struct inode *inode = bdev_inode(bdev);
>>   	int err;
> 
> The uses of 'inode' in this function are
>          filemap_invalidate_lock(inode->i_mapping);
> and
>          filemap_invalidate_unlock(inode->i_mapping);
> 
> IOW, you want bdev_mapping(bdev), not bdev_inode(bdev).
> 
>> @@ -166,7 +166,7 @@ static int blk_ioctl_zeroout(struct block_device *bdev, blk_mode_t mode,
>>   {
>>   	uint64_t range[2];
>>   	uint64_t start, end, len;
>> -	struct inode *inode = bdev->bd_inode;
>> +	struct inode *inode = bdev_inode(bdev);
> 
> Same story.

Yes.

Thanks for the suggestions!
Kuai

> .
>
Christian Brauner April 11, 2024, 11:12 a.m. UTC | #3 
On Sun, Apr 07, 2024 at 10:37:08AM +0800, Yu Kuai wrote:
> Hi,
> 
> 在 2024/04/07 10:22, Al Viro 写道:
> > On Sat, Apr 06, 2024 at 05:09:08PM +0800, Yu Kuai wrote:
> > > @@ -669,7 +669,7 @@ static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
> > >   {
> > >   	struct file *file = iocb->ki_filp;
> > >   	struct block_device *bdev = I_BDEV(file->f_mapping->host);
> > > -	struct inode *bd_inode = bdev->bd_inode;
> > > +	struct inode *bd_inode = bdev_inode(bdev);
> > 
> > What you want here is this:
> > 
> > 	struct inode *bd_inode = file->f_mapping->host;
> > 	struct block_device *bdev = I_BDEV(bd_inode);
> 
> Yes, this way is better, logically.
> > 
> > 
> > > --- a/block/ioctl.c
> > > +++ b/block/ioctl.c
> > > @@ -97,7 +97,7 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
> > >   {
> > >   	uint64_t range[2];
> > >   	uint64_t start, len;
> > > -	struct inode *inode = bdev->bd_inode;
> > > +	struct inode *inode = bdev_inode(bdev);
> > >   	int err;
> > 
> > The uses of 'inode' in this function are
> >          filemap_invalidate_lock(inode->i_mapping);
> > and
> >          filemap_invalidate_unlock(inode->i_mapping);
> > 
> > IOW, you want bdev_mapping(bdev), not bdev_inode(bdev).
> > 
> > > @@ -166,7 +166,7 @@ static int blk_ioctl_zeroout(struct block_device *bdev, blk_mode_t mode,
> > >   {
> > >   	uint64_t range[2];
> > >   	uint64_t start, end, len;
> > > -	struct inode *inode = bdev->bd_inode;
> > > +	struct inode *inode = bdev_inode(bdev);
> > 
> > Same story.
> 
> Yes.

I've folded in those changes during applying.
diff mbox series

Patch

diff --git a/block/bdev.c b/block/bdev.c
index d53bf2f46b43..c0b30392563a 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -43,6 +43,21 @@  static inline struct bdev_inode *BDEV_I(struct inode *inode)
 	return container_of(inode, struct bdev_inode, vfs_inode);
 }
 
+static inline struct bdev_inode *BDEV_B(struct block_device *bdev)
+{
+	return container_of(bdev, struct bdev_inode, bdev);
+}
+
+struct inode *bdev_inode(struct block_device *bdev)
+{
+	return &BDEV_B(bdev)->vfs_inode;
+}
+
+struct address_space *bdev_mapping(struct block_device *bdev)
+{
+	return BDEV_B(bdev)->vfs_inode.i_mapping;
+}
+
 struct block_device *I_BDEV(struct inode *inode)
 {
 	return &BDEV_I(inode)->bdev;
@@ -57,7 +72,7 @@  EXPORT_SYMBOL(file_bdev);
 
 static void bdev_write_inode(struct block_device *bdev)
 {
-	struct inode *inode = bdev->bd_inode;
+	struct inode *inode = bdev_inode(bdev);
 	int ret;
 
 	spin_lock(&inode->i_lock);
@@ -76,7 +91,7 @@  static void bdev_write_inode(struct block_device *bdev)
 /* Kill _all_ buffers and pagecache , dirty or not.. */
 static void kill_bdev(struct block_device *bdev)
 {
-	struct address_space *mapping = bdev->bd_inode->i_mapping;
+	struct address_space *mapping = bdev_mapping(bdev);
 
 	if (mapping_empty(mapping))
 		return;
@@ -88,7 +103,7 @@  static void kill_bdev(struct block_device *bdev)
 /* Invalidate clean unused buffers and pagecache. */
 void invalidate_bdev(struct block_device *bdev)
 {
-	struct address_space *mapping = bdev->bd_inode->i_mapping;
+	struct address_space *mapping = bdev_mapping(bdev);
 
 	if (mapping->nrpages) {
 		invalidate_bh_lrus();
@@ -116,7 +131,7 @@  int truncate_bdev_range(struct block_device *bdev, blk_mode_t mode,
 			goto invalidate;
 	}
 
-	truncate_inode_pages_range(bdev->bd_inode->i_mapping, lstart, lend);
+	truncate_inode_pages_range(bdev_mapping(bdev), lstart, lend);
 	if (!(mode & BLK_OPEN_EXCL))
 		bd_abort_claiming(bdev, truncate_bdev_range);
 	return 0;
@@ -126,7 +141,7 @@  int truncate_bdev_range(struct block_device *bdev, blk_mode_t mode,
 	 * Someone else has handle exclusively open. Try invalidating instead.
 	 * The 'end' argument is inclusive so the rounding is safe.
 	 */
-	return invalidate_inode_pages2_range(bdev->bd_inode->i_mapping,
+	return invalidate_inode_pages2_range(bdev_mapping(bdev),
 					     lstart >> PAGE_SHIFT,
 					     lend >> PAGE_SHIFT);
 }
@@ -134,14 +149,14 @@  int truncate_bdev_range(struct block_device *bdev, blk_mode_t mode,
 static void set_init_blocksize(struct block_device *bdev)
 {
 	unsigned int bsize = bdev_logical_block_size(bdev);
-	loff_t size = i_size_read(bdev->bd_inode);
+	loff_t size = i_size_read(bdev_inode(bdev));
 
 	while (bsize < PAGE_SIZE) {
 		if (size & bsize)
 			break;
 		bsize <<= 1;
 	}
-	bdev->bd_inode->i_blkbits = blksize_bits(bsize);
+	bdev_inode(bdev)->i_blkbits = blksize_bits(bsize);
 }
 
 int set_blocksize(struct block_device *bdev, int size)
@@ -155,9 +170,9 @@  int set_blocksize(struct block_device *bdev, int size)
 		return -EINVAL;
 
 	/* Don't change the size if it is same as current */
-	if (bdev->bd_inode->i_blkbits != blksize_bits(size)) {
+	if (bdev_inode(bdev)->i_blkbits != blksize_bits(size)) {
 		sync_blockdev(bdev);
-		bdev->bd_inode->i_blkbits = blksize_bits(size);
+		bdev_inode(bdev)->i_blkbits = blksize_bits(size);
 		kill_bdev(bdev);
 	}
 	return 0;
@@ -196,7 +211,7 @@  int sync_blockdev(struct block_device *bdev)
 {
 	if (!bdev)
 		return 0;
-	return filemap_write_and_wait(bdev->bd_inode->i_mapping);
+	return filemap_write_and_wait(bdev_mapping(bdev));
 }
 EXPORT_SYMBOL(sync_blockdev);
 
@@ -415,19 +430,22 @@  struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
 void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors)
 {
 	spin_lock(&bdev->bd_size_lock);
-	i_size_write(bdev->bd_inode, (loff_t)sectors << SECTOR_SHIFT);
+	i_size_write(bdev_inode(bdev), (loff_t)sectors << SECTOR_SHIFT);
 	bdev->bd_nr_sectors = sectors;
 	spin_unlock(&bdev->bd_size_lock);
 }
 
 void bdev_add(struct block_device *bdev, dev_t dev)
 {
+	struct inode *inode;
+
 	if (bdev_stable_writes(bdev))
-		mapping_set_stable_writes(bdev->bd_inode->i_mapping);
+		mapping_set_stable_writes(bdev_mapping(bdev));
 	bdev->bd_dev = dev;
-	bdev->bd_inode->i_rdev = dev;
-	bdev->bd_inode->i_ino = dev;
-	insert_inode_hash(bdev->bd_inode);
+	inode = bdev_inode(bdev);
+	inode->i_rdev = dev;
+	inode->i_ino = dev;
+	insert_inode_hash(inode);
 }
 
 long nr_blockdev_pages(void)
@@ -893,7 +911,7 @@  int bdev_open(struct block_device *bdev, blk_mode_t mode, void *holder,
 		bdev_file->f_mode |= FMODE_NOWAIT;
 	if (mode & BLK_OPEN_RESTRICT_WRITES)
 		bdev_file->f_mode |= FMODE_WRITE_RESTRICTED;
-	bdev_file->f_mapping = bdev->bd_inode->i_mapping;
+	bdev_file->f_mapping = bdev_mapping(bdev);
 	bdev_file->f_wb_err = filemap_sample_wb_err(bdev_file->f_mapping);
 	bdev_file->private_data = holder;
 
@@ -955,13 +973,13 @@  struct file *bdev_file_open_by_dev(dev_t dev, blk_mode_t mode, void *holder,
 		return ERR_PTR(-ENXIO);
 
 	flags = blk_to_file_flags(mode);
-	bdev_file = alloc_file_pseudo_noaccount(bdev->bd_inode,
+	bdev_file = alloc_file_pseudo_noaccount(bdev_inode(bdev),
 			blockdev_mnt, "", flags | O_LARGEFILE, &def_blk_fops);
 	if (IS_ERR(bdev_file)) {
 		blkdev_put_no_open(bdev);
 		return bdev_file;
 	}
-	ihold(bdev->bd_inode);
+	ihold(bdev_inode(bdev));
 
 	ret = bdev_open(bdev, mode, holder, hops, bdev_file);
 	if (ret) {
@@ -1238,13 +1256,13 @@  void bdev_statx_dioalign(struct inode *inode, struct kstat *stat)
 
 bool disk_live(struct gendisk *disk)
 {
-	return !inode_unhashed(disk->part0->bd_inode);
+	return !inode_unhashed(bdev_inode(disk->part0));
 }
 EXPORT_SYMBOL_GPL(disk_live);
 
 unsigned int block_size(struct block_device *bdev)
 {
-	return 1 << bdev->bd_inode->i_blkbits;
+	return 1 << bdev_inode(bdev)->i_blkbits;
 }
 EXPORT_SYMBOL_GPL(block_size);
 
diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index da0f4b2a8fa0..7e6805250317 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -398,7 +398,7 @@  int blkdev_zone_mgmt_ioctl(struct block_device *bdev, blk_mode_t mode,
 		op = REQ_OP_ZONE_RESET;
 
 		/* Invalidate the page cache, including dirty pages. */
-		filemap_invalidate_lock(bdev->bd_inode->i_mapping);
+		filemap_invalidate_lock(bdev_mapping(bdev));
 		ret = blkdev_truncate_zone_range(bdev, mode, &zrange);
 		if (ret)
 			goto fail;
@@ -420,7 +420,7 @@  int blkdev_zone_mgmt_ioctl(struct block_device *bdev, blk_mode_t mode,
 
 fail:
 	if (cmd == BLKRESETZONE)
-		filemap_invalidate_unlock(bdev->bd_inode->i_mapping);
+		filemap_invalidate_unlock(bdev_mapping(bdev));
 
 	return ret;
 }
diff --git a/block/blk.h b/block/blk.h
index 5cac4e29ae17..a34bb590cce6 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -427,6 +427,8 @@  static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev,
 }
 #endif /* CONFIG_BLK_DEV_ZONED */
 
+struct inode *bdev_inode(struct block_device *bdev);
+struct address_space *bdev_mapping(struct block_device *bdev);
 struct block_device *bdev_alloc(struct gendisk *disk, u8 partno);
 void bdev_add(struct block_device *bdev, dev_t dev);
 
diff --git a/block/fops.c b/block/fops.c
index af6c244314af..58b427051c0d 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -669,7 +669,7 @@  static ssize_t blkdev_write_iter(struct kiocb *iocb, struct iov_iter *from)
 {
 	struct file *file = iocb->ki_filp;
 	struct block_device *bdev = I_BDEV(file->f_mapping->host);
-	struct inode *bd_inode = bdev->bd_inode;
+	struct inode *bd_inode = bdev_inode(bdev);
 	loff_t size = bdev_nr_bytes(bdev);
 	size_t shorted = 0;
 	ssize_t ret;
diff --git a/block/genhd.c b/block/genhd.c
index bb29a68e1d67..9a7d1b7e9e95 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -656,7 +656,7 @@  void del_gendisk(struct gendisk *disk)
 	 */
 	mutex_lock(&disk->open_mutex);
 	xa_for_each(&disk->part_tbl, idx, part)
-		remove_inode_hash(part->bd_inode);
+		remove_inode_hash(bdev_inode(part));
 	mutex_unlock(&disk->open_mutex);
 
 	/*
@@ -745,7 +745,7 @@  void invalidate_disk(struct gendisk *disk)
 	struct block_device *bdev = disk->part0;
 
 	invalidate_bdev(bdev);
-	bdev->bd_inode->i_mapping->wb_err = 0;
+	bdev_mapping(bdev)->wb_err = 0;
 	set_capacity(disk, 0);
 }
 EXPORT_SYMBOL(invalidate_disk);
@@ -1191,7 +1191,8 @@  static void disk_release(struct device *dev)
 	if (test_bit(GD_ADDED, &disk->state) && disk->fops->free_disk)
 		disk->fops->free_disk(disk);
 
-	iput(disk->part0->bd_inode);	/* frees the disk */
+	/* frees the disk */
+	iput(bdev_inode(disk->part0));
 }
 
 static int block_uevent(const struct device *dev, struct kobj_uevent_env *env)
@@ -1381,7 +1382,7 @@  struct gendisk *__alloc_disk_node(struct request_queue *q, int node_id,
 out_destroy_part_tbl:
 	xa_destroy(&disk->part_tbl);
 	disk->part0->bd_disk = NULL;
-	iput(disk->part0->bd_inode);
+	iput(bdev_inode(disk->part0));
 out_free_bdi:
 	bdi_put(disk->bdi);
 out_free_bioset:
diff --git a/block/ioctl.c b/block/ioctl.c
index 0c76137adcaa..0f78806abb62 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -97,7 +97,7 @@  static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
 {
 	uint64_t range[2];
 	uint64_t start, len;
-	struct inode *inode = bdev->bd_inode;
+	struct inode *inode = bdev_inode(bdev);
 	int err;
 
 	if (!(mode & BLK_OPEN_WRITE))
@@ -151,12 +151,12 @@  static int blk_ioctl_secure_erase(struct block_device *bdev, blk_mode_t mode,
 	if (start + len > bdev_nr_bytes(bdev))
 		return -EINVAL;
 
-	filemap_invalidate_lock(bdev->bd_inode->i_mapping);
+	filemap_invalidate_lock(bdev_mapping(bdev));
 	err = truncate_bdev_range(bdev, mode, start, start + len - 1);
 	if (!err)
 		err = blkdev_issue_secure_erase(bdev, start >> 9, len >> 9,
 						GFP_KERNEL);
-	filemap_invalidate_unlock(bdev->bd_inode->i_mapping);
+	filemap_invalidate_unlock(bdev_mapping(bdev));
 	return err;
 }
 
@@ -166,7 +166,7 @@  static int blk_ioctl_zeroout(struct block_device *bdev, blk_mode_t mode,
 {
 	uint64_t range[2];
 	uint64_t start, end, len;
-	struct inode *inode = bdev->bd_inode;
+	struct inode *inode = bdev_inode(bdev);
 	int err;
 
 	if (!(mode & BLK_OPEN_WRITE))
diff --git a/block/partitions/core.c b/block/partitions/core.c
index b11e88c82c8c..ddd418758fa4 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -243,7 +243,7 @@  static const struct attribute_group *part_attr_groups[] = {
 static void part_release(struct device *dev)
 {
 	put_disk(dev_to_bdev(dev)->bd_disk);
-	iput(dev_to_bdev(dev)->bd_inode);
+	iput(bdev_inode(dev_to_bdev(dev)));
 }
 
 static int part_uevent(const struct device *dev, struct kobj_uevent_env *env)
@@ -469,7 +469,7 @@  int bdev_del_partition(struct gendisk *disk, int partno)
 	 * Just delete the partition and invalidate it.
 	 */
 
-	remove_inode_hash(part->bd_inode);
+	remove_inode_hash(bdev_inode(part));
 	invalidate_bdev(part);
 	drop_partition(part);
 	ret = 0;
@@ -655,7 +655,7 @@  int bdev_disk_changed(struct gendisk *disk, bool invalidate)
 		 * it cannot be looked up any more even when openers
 		 * still hold references.
 		 */
-		remove_inode_hash(part->bd_inode);
+		remove_inode_hash(bdev_inode(part));
 
 		/*
 		 * If @disk->open_partitions isn't elevated but there's
@@ -704,7 +704,7 @@  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 address_space *mapping = bdev_mapping(state->disk->part0);
 	struct folio *folio;
 
 	if (n >= get_capacity(state->disk)) {