From 39c3b4e7d0a0d8876f29ea078b978b3caa924542 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 11 Apr 2024 15:53:40 +0100
Subject: blkdev_write_iter(): saner way to get inode and bdev

... same as in other methods - bdev_file_inode() and I_BDEV() of that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20240411145346.2516848-5-viro@zeniv.linux.org.uk
Signed-off-by: Christian Brauner <brauner@kernel.org>
---
 block/fops.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

(limited to 'block')

diff --git a/block/fops.c b/block/fops.c
index 679d9b752fe8..9d0f36688a5d 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -668,8 +668,8 @@ static ssize_t blkdev_buffered_write(struct kiocb *iocb, struct iov_iter *from)
 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_file_inode(file);
+	struct block_device *bdev = I_BDEV(bd_inode);
 	loff_t size = bdev_nr_bytes(bdev);
 	size_t shorted = 0;
 	ssize_t ret;
-- 
cgit v1.3.1


From 186ddac2072a8134798d72635d1ed0f29889369d Mon Sep 17 00:00:00 2001
From: Yu Kuai <yukuai3@huawei.com>
Date: Thu, 11 Apr 2024 15:53:43 +0100
Subject: block: move two helpers into bdev.c

disk_live() and block_size() access bd_inode directly, prepare to remove
the field bd_inode from block_device, and only access bd_inode in block
layer.

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20240411145346.2516848-8-viro@zeniv.linux.org.uk
Signed-off-by: Christian Brauner <brauner@kernel.org>
---
 block/bdev.c           | 12 ++++++++++++
 include/linux/blkdev.h | 12 ++----------
 2 files changed, 14 insertions(+), 10 deletions(-)

(limited to 'block')

diff --git a/block/bdev.c b/block/bdev.c
index a89bce368b64..536233ac3e99 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -1257,6 +1257,18 @@ void bdev_statx_dioalign(struct inode *inode, struct kstat *stat)
 	blkdev_put_no_open(bdev);
 }
 
+bool disk_live(struct gendisk *disk)
+{
+	return !inode_unhashed(disk->part0->bd_inode);
+}
+EXPORT_SYMBOL_GPL(disk_live);
+
+unsigned int block_size(struct block_device *bdev)
+{
+	return 1 << bdev->bd_inode->i_blkbits;
+}
+EXPORT_SYMBOL_GPL(block_size);
+
 static int __init setup_bdev_allow_write_mounted(char *str)
 {
 	if (kstrtobool(str, &bdev_allow_write_mounted))
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 20c749b2ebc2..99ac98ed9548 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -211,11 +211,6 @@ struct gendisk {
 	struct blk_independent_access_ranges *ia_ranges;
 };
 
-static inline bool disk_live(struct gendisk *disk)
-{
-	return !inode_unhashed(disk->part0->bd_inode);
-}
-
 /**
  * disk_openers - returns how many openers are there for a disk
  * @disk: disk to check
@@ -1364,11 +1359,6 @@ static inline unsigned int blksize_bits(unsigned int size)
 	return order_base_2(size >> SECTOR_SHIFT) + SECTOR_SHIFT;
 }
 
-static inline unsigned int block_size(struct block_device *bdev)
-{
-	return 1 << bdev->bd_inode->i_blkbits;
-}
-
 int kblockd_schedule_work(struct work_struct *work);
 int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
 
@@ -1536,6 +1526,8 @@ void blkdev_put_no_open(struct block_device *bdev);
 
 struct block_device *I_BDEV(struct inode *inode);
 struct block_device *file_bdev(struct file *bdev_file);
+bool disk_live(struct gendisk *disk);
+unsigned int block_size(struct block_device *bdev);
 
 #ifdef CONFIG_BLOCK
 void invalidate_bdev(struct block_device *bdev);
-- 
cgit v1.3.1


From 2638c20876734f986fd91cfbe196483835ed7095 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sun, 28 Apr 2024 19:01:39 -0400
Subject: missing helpers: bdev_unhash(), bdev_drop()

bdev_unhash(): make block device invisible to lookups by device number
bdev_drop(): drop reference to associated inode.

Both are internal, for use by genhd and partition-related code - similar
to bdev_add().  The logics in there (especially the lifetime-related
parts of it) ought to be cleaned up, but that's a separate story; here
we just encapsulate getting to associated inode.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 block/bdev.c            | 10 ++++++++++
 block/blk.h             |  2 ++
 block/genhd.c           |  6 +++---
 block/partitions/core.c |  6 +++---
 4 files changed, 18 insertions(+), 6 deletions(-)

(limited to 'block')

diff --git a/block/bdev.c b/block/bdev.c
index 536233ac3e99..28e6f0423857 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -451,6 +451,16 @@ void bdev_add(struct block_device *bdev, dev_t dev)
 	insert_inode_hash(bdev->bd_inode);
 }
 
+void bdev_unhash(struct block_device *bdev)
+{
+	remove_inode_hash(bdev->bd_inode);
+}
+
+void bdev_drop(struct block_device *bdev)
+{
+	iput(bdev->bd_inode);
+}
+
 long nr_blockdev_pages(void)
 {
 	struct inode *inode;
diff --git a/block/blk.h b/block/blk.h
index d9f584984bc4..e3347e1030d5 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -428,6 +428,8 @@ static inline int blkdev_zone_mgmt_ioctl(struct block_device *bdev,
 
 struct block_device *bdev_alloc(struct gendisk *disk, u8 partno);
 void bdev_add(struct block_device *bdev, dev_t dev);
+void bdev_unhash(struct block_device *bdev);
+void bdev_drop(struct block_device *bdev);
 
 int blk_alloc_ext_minor(void);
 void blk_free_ext_minor(unsigned int minor);
diff --git a/block/genhd.c b/block/genhd.c
index bb29a68e1d67..93f5118b7d41 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);
+		bdev_unhash(part);
 	mutex_unlock(&disk->open_mutex);
 
 	/*
@@ -1191,7 +1191,7 @@ 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 */
+	bdev_drop(disk->part0);	/* frees the disk */
 }
 
 static int block_uevent(const struct device *dev, struct kobj_uevent_env *env)
@@ -1381,7 +1381,7 @@ out_erase_part0:
 out_destroy_part_tbl:
 	xa_destroy(&disk->part_tbl);
 	disk->part0->bd_disk = NULL;
-	iput(disk->part0->bd_inode);
+	bdev_drop(disk->part0);
 out_free_bdi:
 	bdi_put(disk->bdi);
 out_free_bioset:
diff --git a/block/partitions/core.c b/block/partitions/core.c
index b11e88c82c8c..2b75e325c63b 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);
+	bdev_drop(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);
+	bdev_unhash(part);
 	invalidate_bdev(part);
 	drop_partition(part);
 	ret = 0;
@@ -655,7 +655,7 @@ rescan:
 		 * it cannot be looked up any more even when openers
 		 * still hold references.
 		 */
-		remove_inode_hash(part->bd_inode);
+		bdev_unhash(part);
 
 		/*
 		 * If @disk->open_partitions isn't elevated but there's
-- 
cgit v1.3.1


From e33aef2c58577f51ec22736843a652576ce0ef7a Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 11 Apr 2024 15:53:36 +0100
Subject: block_device: add a pointer to struct address_space (page cache of
 bdev)

points to ->i_data of coallocated inode.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20240411145346.2516848-1-viro@zeniv.linux.org.uk
Signed-off-by: Christian Brauner <brauner@kernel.org>
---
 block/bdev.c              | 1 +
 include/linux/blk_types.h | 1 +
 2 files changed, 2 insertions(+)

(limited to 'block')

diff --git a/block/bdev.c b/block/bdev.c
index 28e6f0423857..8e19101cbbb0 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -419,6 +419,7 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
 	mutex_init(&bdev->bd_holder_lock);
 	bdev->bd_partno = partno;
 	bdev->bd_inode = inode;
+	bdev->bd_mapping = &inode->i_data;
 	bdev->bd_queue = disk->queue;
 	if (partno)
 		bdev->bd_has_submit_bio = disk->part0->bd_has_submit_bio;
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index cb1526ec44b5..6438c75cbb35 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -51,6 +51,7 @@ struct block_device {
 	bool			bd_has_submit_bio;
 	dev_t			bd_dev;
 	struct inode		*bd_inode;	/* will die */
+	struct address_space	*bd_mapping;	/* page cache */
 
 	atomic_t		bd_openers;
 	spinlock_t		bd_size_lock; /* for bd_inode->i_size updates */
-- 
cgit v1.3.1


From 224941e8379a0de8652ffec768cc8394f0b1cb95 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 11 Apr 2024 15:53:37 +0100
Subject: use ->bd_mapping instead of ->bd_inode->i_mapping

Just the low-hanging fruit...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20240411145346.2516848-2-viro@zeniv.linux.org.uk
Signed-off-by: Christian Brauner <brauner@kernel.org>
---
 block/bdev.c                | 18 +++++++++---------
 block/blk-zoned.c           |  4 ++--
 block/genhd.c               |  2 +-
 block/ioctl.c               |  4 ++--
 block/partitions/core.c     |  2 +-
 drivers/md/bcache/super.c   |  2 +-
 drivers/scsi/scsicam.c      |  2 +-
 fs/btrfs/disk-io.c          |  6 +++---
 fs/btrfs/volumes.c          |  2 +-
 fs/btrfs/zoned.c            |  2 +-
 fs/buffer.c                 |  2 +-
 fs/cramfs/inode.c           |  2 +-
 fs/erofs/data.c             |  2 +-
 fs/ext4/dir.c               |  2 +-
 fs/ext4/ext4_jbd2.c         |  2 +-
 fs/ext4/super.c             |  6 +++---
 fs/jbd2/journal.c           |  2 +-
 include/linux/buffer_head.h |  4 ++--
 include/linux/jbd2.h        |  4 ++--
 19 files changed, 35 insertions(+), 35 deletions(-)

(limited to 'block')

diff --git a/block/bdev.c b/block/bdev.c
index 8e19101cbbb0..00017af92a51 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -76,7 +76,7 @@ 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->bd_mapping;
 
 	if (mapping_empty(mapping))
 		return;
@@ -88,7 +88,7 @@ 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->bd_mapping;
 
 	if (mapping->nrpages) {
 		invalidate_bh_lrus();
@@ -116,7 +116,7 @@ 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->bd_mapping, lstart, lend);
 	if (!(mode & BLK_OPEN_EXCL))
 		bd_abort_claiming(bdev, truncate_bdev_range);
 	return 0;
@@ -126,7 +126,7 @@ invalidate:
 	 * 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->bd_mapping,
 					     lstart >> PAGE_SHIFT,
 					     lend >> PAGE_SHIFT);
 }
@@ -198,7 +198,7 @@ int sync_blockdev_nowait(struct block_device *bdev)
 {
 	if (!bdev)
 		return 0;
-	return filemap_flush(bdev->bd_inode->i_mapping);
+	return filemap_flush(bdev->bd_mapping);
 }
 EXPORT_SYMBOL_GPL(sync_blockdev_nowait);
 
@@ -210,13 +210,13 @@ 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->bd_mapping);
 }
 EXPORT_SYMBOL(sync_blockdev);
 
 int sync_blockdev_range(struct block_device *bdev, loff_t lstart, loff_t lend)
 {
-	return filemap_write_and_wait_range(bdev->bd_inode->i_mapping,
+	return filemap_write_and_wait_range(bdev->bd_mapping,
 			lstart, lend);
 }
 EXPORT_SYMBOL(sync_blockdev_range);
@@ -445,7 +445,7 @@ void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors)
 void bdev_add(struct block_device *bdev, dev_t dev)
 {
 	if (bdev_stable_writes(bdev))
-		mapping_set_stable_writes(bdev->bd_inode->i_mapping);
+		mapping_set_stable_writes(bdev->bd_mapping);
 	bdev->bd_dev = dev;
 	bdev->bd_inode->i_rdev = dev;
 	bdev->bd_inode->i_ino = dev;
@@ -925,7 +925,7 @@ 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->bd_mapping;
 	bdev_file->f_wb_err = filemap_sample_wb_err(bdev_file->f_mapping);
 	bdev_file->private_data = holder;
 
diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index da0f4b2a8fa0..b008bcd4889c 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->bd_mapping);
 		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->bd_mapping);
 
 	return ret;
 }
diff --git a/block/genhd.c b/block/genhd.c
index 93f5118b7d41..2bf05bd0f071 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -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->bd_mapping->wb_err = 0;
 	set_capacity(disk, 0);
 }
 EXPORT_SYMBOL(invalidate_disk);
diff --git a/block/ioctl.c b/block/ioctl.c
index 1c800364bc70..7c13d8bed453 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -152,12 +152,12 @@ 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->bd_mapping);
 	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->bd_mapping);
 	return err;
 }
 
diff --git a/block/partitions/core.c b/block/partitions/core.c
index 2b75e325c63b..63ee317dfff0 100644
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -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 = state->disk->part0->bd_mapping;
 	struct folio *folio;
 
 	if (n >= get_capacity(state->disk)) {
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 0ee5e17ae2dd..277ad958cf53 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -171,7 +171,7 @@ static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
 	struct page *page;
 	unsigned int i;
 
-	page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
+	page = read_cache_page_gfp(bdev->bd_mapping,
 				   SB_OFFSET >> PAGE_SHIFT, GFP_KERNEL);
 	if (IS_ERR(page))
 		return "IO error";
diff --git a/drivers/scsi/scsicam.c b/drivers/scsi/scsicam.c
index e2c7d8ef205f..dd69342bbe78 100644
--- a/drivers/scsi/scsicam.c
+++ b/drivers/scsi/scsicam.c
@@ -32,7 +32,7 @@
  */
 unsigned char *scsi_bios_ptable(struct block_device *dev)
 {
-	struct address_space *mapping = bdev_whole(dev)->bd_inode->i_mapping;
+	struct address_space *mapping = bdev_whole(dev)->bd_mapping;
 	unsigned char *res = NULL;
 	struct folio *folio;
 
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 3df5477d48a8..f10e894b0bf5 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -3651,7 +3651,7 @@ struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
 	struct btrfs_super_block *super;
 	struct page *page;
 	u64 bytenr, bytenr_orig;
-	struct address_space *mapping = bdev->bd_inode->i_mapping;
+	struct address_space *mapping = bdev->bd_mapping;
 	int ret;
 
 	bytenr_orig = btrfs_sb_offset(copy_num);
@@ -3738,7 +3738,7 @@ static int write_dev_supers(struct btrfs_device *device,
 			    struct btrfs_super_block *sb, int max_mirrors)
 {
 	struct btrfs_fs_info *fs_info = device->fs_info;
-	struct address_space *mapping = device->bdev->bd_inode->i_mapping;
+	struct address_space *mapping = device->bdev->bd_mapping;
 	SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
 	int i;
 	int errors = 0;
@@ -3855,7 +3855,7 @@ static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
 		    device->commit_total_bytes)
 			break;
 
-		page = find_get_page(device->bdev->bd_inode->i_mapping,
+		page = find_get_page(device->bdev->bd_mapping,
 				     bytenr >> PAGE_SHIFT);
 		if (!page) {
 			errors++;
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 65c03ddecc59..33d357e5f9c5 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1290,7 +1290,7 @@ static struct btrfs_super_block *btrfs_read_disk_super(struct block_device *bdev
 		return ERR_PTR(-EINVAL);
 
 	/* pull in the page with our super */
-	page = read_cache_page_gfp(bdev->bd_inode->i_mapping, index, GFP_KERNEL);
+	page = read_cache_page_gfp(bdev->bd_mapping, index, GFP_KERNEL);
 
 	if (IS_ERR(page))
 		return ERR_CAST(page);
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 4cba80b34387..9b43fa493219 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -118,7 +118,7 @@ static int sb_write_pointer(struct block_device *bdev, struct blk_zone *zones,
 		return -ENOENT;
 	} else if (full[0] && full[1]) {
 		/* Compare two super blocks */
-		struct address_space *mapping = bdev->bd_inode->i_mapping;
+		struct address_space *mapping = bdev->bd_mapping;
 		struct page *page[BTRFS_NR_SB_LOG_ZONES];
 		struct btrfs_super_block *super[BTRFS_NR_SB_LOG_ZONES];
 		int i;
diff --git a/fs/buffer.c b/fs/buffer.c
index 4f73d23c2c46..d5a0932ae68d 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1463,7 +1463,7 @@ __bread_gfp(struct block_device *bdev, sector_t block,
 {
 	struct buffer_head *bh;
 
-	gfp |= mapping_gfp_constraint(bdev->bd_inode->i_mapping, ~__GFP_FS);
+	gfp |= mapping_gfp_constraint(bdev->bd_mapping, ~__GFP_FS);
 
 	/*
 	 * Prefer looping in the allocator rather than here, at least that
diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index 9901057a15ba..460690ca0174 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -183,7 +183,7 @@ static int next_buffer;
 static void *cramfs_blkdev_read(struct super_block *sb, unsigned int offset,
 				unsigned int len)
 {
-	struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
+	struct address_space *mapping = sb->s_bdev->bd_mapping;
 	struct file_ra_state ra = {};
 	struct page *pages[BLKS_PER_BUF];
 	unsigned i, blocknr, buffer;
diff --git a/fs/erofs/data.c b/fs/erofs/data.c
index e1a170e45c70..5fc03c1e2757 100644
--- a/fs/erofs/data.c
+++ b/fs/erofs/data.c
@@ -68,7 +68,7 @@ void erofs_init_metabuf(struct erofs_buf *buf, struct super_block *sb)
 	if (erofs_is_fscache_mode(sb))
 		buf->mapping = EROFS_SB(sb)->s_fscache->inode->i_mapping;
 	else
-		buf->mapping = sb->s_bdev->bd_inode->i_mapping;
+		buf->mapping = sb->s_bdev->bd_mapping;
 }
 
 void *erofs_read_metabuf(struct erofs_buf *buf, struct super_block *sb,
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c
index 3985f8c33f95..ff4514e4626b 100644
--- a/fs/ext4/dir.c
+++ b/fs/ext4/dir.c
@@ -192,7 +192,7 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx)
 					(PAGE_SHIFT - inode->i_blkbits);
 			if (!ra_has_index(&file->f_ra, index))
 				page_cache_sync_readahead(
-					sb->s_bdev->bd_inode->i_mapping,
+					sb->s_bdev->bd_mapping,
 					&file->f_ra, file,
 					index, 1);
 			file->f_ra.prev_pos = (loff_t)index << PAGE_SHIFT;
diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c
index 5d8055161acd..da4a82456383 100644
--- a/fs/ext4/ext4_jbd2.c
+++ b/fs/ext4/ext4_jbd2.c
@@ -206,7 +206,7 @@ static void ext4_journal_abort_handle(const char *caller, unsigned int line,
 
 static void ext4_check_bdev_write_error(struct super_block *sb)
 {
-	struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
+	struct address_space *mapping = sb->s_bdev->bd_mapping;
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
 	int err;
 
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index b255f798f449..02042eb91806 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -244,7 +244,7 @@ static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 				   blk_opf_t op_flags)
 {
-	gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_inode->i_mapping,
+	gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_mapping,
 			~__GFP_FS) | __GFP_MOVABLE;
 
 	return __ext4_sb_bread_gfp(sb, block, op_flags, gfp);
@@ -253,7 +253,7 @@ struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
 					    sector_t block)
 {
-	gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_inode->i_mapping,
+	gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_mapping,
 			~__GFP_FS);
 
 	return __ext4_sb_bread_gfp(sb, block, 0, gfp);
@@ -5556,7 +5556,7 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
 	 * used to detect the metadata async write error.
 	 */
 	spin_lock_init(&sbi->s_bdev_wb_lock);
-	errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
+	errseq_check_and_advance(&sb->s_bdev->bd_mapping->wb_err,
 				 &sbi->s_bdev_wb_err);
 	EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
 	ext4_orphan_cleanup(sb, es);
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index b6c114c11b97..03c4b9214f56 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -2009,7 +2009,7 @@ static int __jbd2_journal_erase(journal_t *journal, unsigned int flags)
 		byte_count = (block_stop - block_start + 1) *
 				journal->j_blocksize;
 
-		truncate_inode_pages_range(journal->j_dev->bd_inode->i_mapping,
+		truncate_inode_pages_range(journal->j_dev->bd_mapping,
 				byte_start, byte_stop);
 
 		if (flags & JBD2_JOURNAL_FLUSH_DISCARD) {
diff --git a/include/linux/buffer_head.h b/include/linux/buffer_head.h
index d78454a4dd1f..e58a0d63409a 100644
--- a/include/linux/buffer_head.h
+++ b/include/linux/buffer_head.h
@@ -338,7 +338,7 @@ static inline struct buffer_head *getblk_unmovable(struct block_device *bdev,
 {
 	gfp_t gfp;
 
-	gfp = mapping_gfp_constraint(bdev->bd_inode->i_mapping, ~__GFP_FS);
+	gfp = mapping_gfp_constraint(bdev->bd_mapping, ~__GFP_FS);
 	gfp |= __GFP_NOFAIL;
 
 	return bdev_getblk(bdev, block, size, gfp);
@@ -349,7 +349,7 @@ static inline struct buffer_head *__getblk(struct block_device *bdev,
 {
 	gfp_t gfp;
 
-	gfp = mapping_gfp_constraint(bdev->bd_inode->i_mapping, ~__GFP_FS);
+	gfp = mapping_gfp_constraint(bdev->bd_mapping, ~__GFP_FS);
 	gfp |= __GFP_MOVABLE | __GFP_NOFAIL;
 
 	return bdev_getblk(bdev, block, size, gfp);
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 971f3e826e15..ac31c37816f7 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -1696,7 +1696,7 @@ static inline void jbd2_journal_abort_handle(handle_t *handle)
 
 static inline void jbd2_init_fs_dev_write_error(journal_t *journal)
 {
-	struct address_space *mapping = journal->j_fs_dev->bd_inode->i_mapping;
+	struct address_space *mapping = journal->j_fs_dev->bd_mapping;
 
 	/*
 	 * Save the original wb_err value of client fs's bdev mapping which
@@ -1707,7 +1707,7 @@ static inline void jbd2_init_fs_dev_write_error(journal_t *journal)
 
 static inline int jbd2_check_fs_dev_write_error(journal_t *journal)
 {
-	struct address_space *mapping = journal->j_fs_dev->bd_inode->i_mapping;
+	struct address_space *mapping = journal->j_fs_dev->bd_mapping;
 
 	return errseq_check(&mapping->wb_err,
 			    READ_ONCE(journal->j_fs_dev_wb_err));
-- 
cgit v1.3.1


From 881494ed031f60d48041549368989a37405a7e50 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 11 Apr 2024 15:53:41 +0100
Subject: blk_ioctl_{discard,zeroout}(): we only want ->bd_inode->i_mapping
 here...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20240411145346.2516848-6-viro@zeniv.linux.org.uk
Signed-off-by: Christian Brauner <brauner@kernel.org>
---
 block/ioctl.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

(limited to 'block')

diff --git a/block/ioctl.c b/block/ioctl.c
index 7c13d8bed453..831d6350ca25 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -97,7 +97,6 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
 {
 	uint64_t range[2];
 	uint64_t start, len, end;
-	struct inode *inode = bdev->bd_inode;
 	int err;
 
 	if (!(mode & BLK_OPEN_WRITE))
@@ -121,13 +120,13 @@ static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
 	    end > bdev_nr_bytes(bdev))
 		return -EINVAL;
 
-	filemap_invalidate_lock(inode->i_mapping);
+	filemap_invalidate_lock(bdev->bd_mapping);
 	err = truncate_bdev_range(bdev, mode, start, start + len - 1);
 	if (err)
 		goto fail;
 	err = blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL);
 fail:
-	filemap_invalidate_unlock(inode->i_mapping);
+	filemap_invalidate_unlock(bdev->bd_mapping);
 	return err;
 }
 
@@ -167,7 +166,6 @@ 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;
 	int err;
 
 	if (!(mode & BLK_OPEN_WRITE))
@@ -190,7 +188,7 @@ static int blk_ioctl_zeroout(struct block_device *bdev, blk_mode_t mode,
 		return -EINVAL;
 
 	/* Invalidate the page cache, including dirty pages */
-	filemap_invalidate_lock(inode->i_mapping);
+	filemap_invalidate_lock(bdev->bd_mapping);
 	err = truncate_bdev_range(bdev, mode, start, end);
 	if (err)
 		goto fail;
@@ -199,7 +197,7 @@ static int blk_ioctl_zeroout(struct block_device *bdev, blk_mode_t mode,
 				   BLKDEV_ZERO_NOUNMAP);
 
 fail:
-	filemap_invalidate_unlock(inode->i_mapping);
+	filemap_invalidate_unlock(bdev->bd_mapping);
 	return err;
 }
 
-- 
cgit v1.3.1


From df65f1660b6141f0b051d2439cc99222a6ae865b Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sun, 28 Apr 2024 19:09:12 -0400
Subject: block/bdev.c: use the knowledge of inode/bdev coallocation

Here we know that bdevfs inodes are coallocated with struct block_device
and we can get to ->bd_inode value without any dereferencing.  Introduce
an inlined helper (static, *not* exported, purely internal for bdev.c)
that gets an associated inode by block_device - BD_INODE(bdev).

NOTE: leave it static; nobody outside of block/bdev.c has any business
playing with that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 block/bdev.c | 32 +++++++++++++++++++-------------
 1 file changed, 19 insertions(+), 13 deletions(-)

(limited to 'block')

diff --git a/block/bdev.c b/block/bdev.c
index 00017af92a51..a8c66cc1d6b8 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -43,6 +43,11 @@ static inline struct bdev_inode *BDEV_I(struct inode *inode)
 	return container_of(inode, struct bdev_inode, vfs_inode);
 }
 
+static inline struct inode *BD_INODE(struct block_device *bdev)
+{
+	return &container_of(bdev, struct bdev_inode, bdev)->vfs_inode;
+}
+
 struct block_device *I_BDEV(struct inode *inode)
 {
 	return &BDEV_I(inode)->bdev;
@@ -57,7 +62,7 @@ EXPORT_SYMBOL(file_bdev);
 
 static void bdev_write_inode(struct block_device *bdev)
 {
-	struct inode *inode = bdev->bd_inode;
+	struct inode *inode = BD_INODE(bdev);
 	int ret;
 
 	spin_lock(&inode->i_lock);
@@ -134,14 +139,14 @@ invalidate:
 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(BD_INODE(bdev));
 
 	while (bsize < PAGE_SIZE) {
 		if (size & bsize)
 			break;
 		bsize <<= 1;
 	}
-	bdev->bd_inode->i_blkbits = blksize_bits(bsize);
+	BD_INODE(bdev)->i_blkbits = blksize_bits(bsize);
 }
 
 int set_blocksize(struct file *file, int size)
@@ -437,29 +442,30 @@ 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(BD_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 = BD_INODE(bdev);
 	if (bdev_stable_writes(bdev))
 		mapping_set_stable_writes(bdev->bd_mapping);
 	bdev->bd_dev = dev;
-	bdev->bd_inode->i_rdev = dev;
-	bdev->bd_inode->i_ino = dev;
-	insert_inode_hash(bdev->bd_inode);
+	inode->i_rdev = dev;
+	inode->i_ino = dev;
+	insert_inode_hash(inode);
 }
 
 void bdev_unhash(struct block_device *bdev)
 {
-	remove_inode_hash(bdev->bd_inode);
+	remove_inode_hash(BD_INODE(bdev));
 }
 
 void bdev_drop(struct block_device *bdev)
 {
-	iput(bdev->bd_inode);
+	iput(BD_INODE(bdev));
 }
 
 long nr_blockdev_pages(void)
@@ -987,13 +993,13 @@ 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(BD_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(BD_INODE(bdev));
 
 	ret = bdev_open(bdev, mode, holder, hops, bdev_file);
 	if (ret) {
@@ -1270,13 +1276,13 @@ 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(BD_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 << BD_INODE(bdev)->i_blkbits;
 }
 EXPORT_SYMBOL_GPL(block_size);
 
-- 
cgit v1.3.1


From 203c1ce0bb063d1620698e39637b64f2d09c1368 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sun, 28 Apr 2024 20:47:14 -0400
Subject: RIP ->bd_inode

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 block/bdev.c              | 1 -
 include/linux/blk_types.h | 1 -
 2 files changed, 2 deletions(-)

(limited to 'block')

diff --git a/block/bdev.c b/block/bdev.c
index a8c66cc1d6b8..0849a9cfa2b6 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -423,7 +423,6 @@ struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
 	spin_lock_init(&bdev->bd_size_lock);
 	mutex_init(&bdev->bd_holder_lock);
 	bdev->bd_partno = partno;
-	bdev->bd_inode = inode;
 	bdev->bd_mapping = &inode->i_data;
 	bdev->bd_queue = disk->queue;
 	if (partno)
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 6438c75cbb35..5616d059cb23 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -50,7 +50,6 @@ struct block_device {
 	bool			bd_write_holder;
 	bool			bd_has_submit_bio;
 	dev_t			bd_dev;
-	struct inode		*bd_inode;	/* will die */
 	struct address_space	*bd_mapping;	/* page cache */
 
 	atomic_t		bd_openers;
-- 
cgit v1.3.1